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Weng W, Deng Y, Deviatiiarov R, Hamidi S, Kajikawa E, Gusev O, Kiyonari H, Zhang G, Sheng G. ETV2 induces endothelial, but not hematopoietic, lineage specification in birds. Life Sci Alliance 2024; 7:e202402694. [PMID: 38570190 PMCID: PMC10992995 DOI: 10.26508/lsa.202402694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 03/27/2024] [Accepted: 03/28/2024] [Indexed: 04/05/2024] Open
Abstract
Cardiovascular system develops from the lateral plate mesoderm. Its three primary cell lineages (hematopoietic, endothelial, and muscular) are specified by the sequential actions of conserved transcriptional factors. ETV2, a master regulator of mammalian hemangioblast development, however, is absent in the chicken genome and acts downstream of NPAS4L in zebrafish. Here, we investigated the epistatic relationship between NPAS4L and ETV2 in avian hemangioblast development. We showed that ETV2 is deleted in all 363 avian genomes analyzed. Mouse ETV2 induced LMO2, but not NPAS4L or SCL, expression in chicken mesoderm. Squamate (lizards, geckos, and snakes) genomes contain both NPAS4L and ETV2 In Madagascar ground gecko, both genes were expressed in developing hemangioblasts. Gecko ETV2 induced only LMO2 in chicken mesoderm. We propose that both NPAS4L and ETV2 were present in ancestral amniote, with ETV2 acting downstream of NPAS4L in endothelial lineage specification. ETV2 may have acted as a pioneer factor by promoting chromatin accessibility of endothelial-specific genes and, in parallel with NPAS4L loss in ancestral mammals, has gained similar function in regulating blood-specific genes.
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Affiliation(s)
- Wei Weng
- https://ror.org/02cgss904 International Research Center for Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Yuan Deng
- Beijing Genome Institute (BGI), Shenzhen, China
| | - Ruslan Deviatiiarov
- https://ror.org/02cgss904 International Research Center for Medical Sciences, Kumamoto University, Kumamoto, Japan
- Graduate School of Medicine, Juntendo University, Tokyo, Japan
- Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
| | - Sofiane Hamidi
- https://ror.org/02cgss904 International Research Center for Medical Sciences, Kumamoto University, Kumamoto, Japan
| | | | - Oleg Gusev
- https://ror.org/02cgss904 International Research Center for Medical Sciences, Kumamoto University, Kumamoto, Japan
- Graduate School of Medicine, Juntendo University, Tokyo, Japan
- Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
- Life Improvement by Future Technologies (LIFT) Center, Moscow, Russia
| | | | - Guojie Zhang
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
- Centre for Evolutionary & Organismal Biology, Zhejiang University, Hangzhou, China
| | - Guojun Sheng
- https://ror.org/02cgss904 International Research Center for Medical Sciences, Kumamoto University, Kumamoto, Japan
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2
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Steimle JD, Kim C, Rowton M, Nadadur RD, Wang Z, Stocker M, Hoffmann AD, Hanson E, Kweon J, Sinha T, Choi K, Black BL, Cunningham JM, Moskowitz IP, Ikegami K. ETV2 primes hematoendothelial gene enhancers prior to hematoendothelial fate commitment. Cell Rep 2023; 42:112665. [PMID: 37330911 PMCID: PMC10592526 DOI: 10.1016/j.celrep.2023.112665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 03/14/2023] [Accepted: 06/02/2023] [Indexed: 06/20/2023] Open
Abstract
Mechanisms underlying distinct specification, commitment, and differentiation phases of cell fate determination remain undefined due to difficulties capturing these processes. Here, we interrogate the activity of ETV2, a transcription factor necessary and sufficient for hematoendothelial differentiation, within isolated fate intermediates. We observe transcriptional upregulation of Etv2 and opening of ETV2-binding sites, indicating new ETV2 binding, in a common cardiac-hematoendothelial progenitor population. Accessible ETV2-binding sites are active at the Etv2 locus but not at other hematoendothelial regulator genes. Hematoendothelial commitment coincides with the activation of a small repertoire of previously accessible ETV2-binding sites at hematoendothelial regulators. Hematoendothelial differentiation accompanies activation of a large repertoire of new ETV2-binding sites and upregulation of hematopoietic and endothelial gene regulatory networks. This work distinguishes specification, commitment, and sublineage differentiation phases of ETV2-dependent transcription and suggests that the shift from ETV2 binding to ETV2-bound enhancer activation, not ETV2 binding to target enhancers, drives hematoendothelial fate commitment.
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Affiliation(s)
- Jeffrey D Steimle
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, IL 60637, USA
| | - Chul Kim
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, IL 60637, USA; Department of Pediatrics, Section of Hematology/Oncology, University of Chicago, Chicago, IL 60637, USA
| | - Megan Rowton
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, IL 60637, USA
| | - Rangarajan D Nadadur
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, IL 60637, USA
| | - Zhezhen Wang
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, IL 60637, USA
| | - Matthew Stocker
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, IL 60637, USA
| | - Andrew D Hoffmann
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, IL 60637, USA
| | - Erika Hanson
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, IL 60637, USA
| | - Junghun Kweon
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, IL 60637, USA
| | - Tanvi Sinha
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Kyunghee Choi
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Brian L Black
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143, USA; Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94143, USA
| | - John M Cunningham
- Department of Pediatrics, Section of Hematology/Oncology, University of Chicago, Chicago, IL 60637, USA
| | - Ivan P Moskowitz
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, IL 60637, USA.
| | - Kohta Ikegami
- Division of Molecular and Cardiovascular Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati, Cincinnati, OH 45229, USA.
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3
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Moya-Jódar M, Coppiello G, Rodríguez-Madoz JR, Abizanda G, Barlabé P, Vilas-Zornoza A, Ullate-Agote A, Luongo C, Rodríguez-Tobón E, Navarro-Serna S, París-Oller E, Oficialdegui M, Carvajal-Vergara X, Ordovás L, Prósper F, García-Vázquez FA, Aranguren XL. One-Step In Vitro Generation of ETV2-Null Pig Embryos. Animals (Basel) 2022; 12:ani12141829. [PMID: 35883376 PMCID: PMC9311767 DOI: 10.3390/ani12141829] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 07/05/2022] [Accepted: 07/14/2022] [Indexed: 11/16/2022] Open
Abstract
Simple Summary One of the latest goals in regenerative medicine is to use pluripotent stem cells to generate whole organs in vivo through the blastocyst complementation technique. This method consists of the microinjection of pluripotent stem cells into preimplantation embryos that have been genetically modified to ablate the development of a target organ. By taking advantage of the spatiotemporal clues present in the developing embryo, pluripotent stem cells are able to colonize the empty developmental niche and create the missing organ. Combining human pluripotent stem cells with genetically engineered pig embryos, it would be possible to obtain humanized organs that could be used for transplantation, and, therefore, solve the worldwide issue of insufficient availability of transplantable organs. As endothelial cells play a critical role in xenotransplantation rejection in all organs, in this study, we optimized a protocol to generate a vascular-disabled preimplantation pig embryo using the CRISPR/Cas9 system. This protocol could be used to generate avascular embryos for blastocyst complementation experiments and work towards the generation of rejection-free humanized organs in pigs. Abstract Each year, tens of thousands of people worldwide die of end-stage organ failure due to the limited availability of organs for use in transplantation. To meet this clinical demand, one of the last frontiers of regenerative medicine is the generation of humanized organs in pigs from pluripotent stem cells (PSCs) via blastocyst complementation. For this, organ-disabled pig models are needed. As endothelial cells (ECs) play a critical role in xenotransplantation rejection in every organ, we aimed to produce hematoendothelial-disabled pig embryos targeting the master transcription factor ETV2 via CRISPR-Cas9-mediated genome modification. In this study, we designed five different guide RNAs (gRNAs) against the DNA-binding domain of the porcine ETV2 gene, which were tested on porcine fibroblasts in vitro. Four out of five guides showed cleavage capacity and, subsequently, these four guides were microinjected individually as ribonucleoprotein complexes (RNPs) into one-cell-stage porcine embryos. Next, we combined the two gRNAs that showed the highest targeting efficiency and microinjected them at higher concentrations. Under these conditions, we significantly improved the rate of biallelic mutation. Hence, here, we describe an efficient one-step method for the generation of hematoendothelial-disabled pig embryos via CRISPR-Cas9 microinjection in zygotes. This model could be used in experimentation related to the in vivo generation of humanized organs.
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Affiliation(s)
- Marta Moya-Jódar
- Program of Regenerative Medicine, Centre for Applied Medical Research (CIMA), Instituto de Investigación Sanitaria de Navarra (IdiSNA), University of Navarra, 31008 Pamplona, Spain; (M.M.-J.); (G.C.); (J.R.R.-M.); (G.A.); (P.B.); (A.U.-A.); (X.C.-V.); (F.P.)
| | - Giulia Coppiello
- Program of Regenerative Medicine, Centre for Applied Medical Research (CIMA), Instituto de Investigación Sanitaria de Navarra (IdiSNA), University of Navarra, 31008 Pamplona, Spain; (M.M.-J.); (G.C.); (J.R.R.-M.); (G.A.); (P.B.); (A.U.-A.); (X.C.-V.); (F.P.)
| | - Juan Roberto Rodríguez-Madoz
- Program of Regenerative Medicine, Centre for Applied Medical Research (CIMA), Instituto de Investigación Sanitaria de Navarra (IdiSNA), University of Navarra, 31008 Pamplona, Spain; (M.M.-J.); (G.C.); (J.R.R.-M.); (G.A.); (P.B.); (A.U.-A.); (X.C.-V.); (F.P.)
| | - Gloria Abizanda
- Program of Regenerative Medicine, Centre for Applied Medical Research (CIMA), Instituto de Investigación Sanitaria de Navarra (IdiSNA), University of Navarra, 31008 Pamplona, Spain; (M.M.-J.); (G.C.); (J.R.R.-M.); (G.A.); (P.B.); (A.U.-A.); (X.C.-V.); (F.P.)
| | - Paula Barlabé
- Program of Regenerative Medicine, Centre for Applied Medical Research (CIMA), Instituto de Investigación Sanitaria de Navarra (IdiSNA), University of Navarra, 31008 Pamplona, Spain; (M.M.-J.); (G.C.); (J.R.R.-M.); (G.A.); (P.B.); (A.U.-A.); (X.C.-V.); (F.P.)
| | - Amaia Vilas-Zornoza
- Advanced Genomics Laboratory, Program of Hemato-Oncology, Center for Applied Medical Research (CIMA), University of Navarra, 31008 Pamplona, Spain;
| | - Asier Ullate-Agote
- Program of Regenerative Medicine, Centre for Applied Medical Research (CIMA), Instituto de Investigación Sanitaria de Navarra (IdiSNA), University of Navarra, 31008 Pamplona, Spain; (M.M.-J.); (G.C.); (J.R.R.-M.); (G.A.); (P.B.); (A.U.-A.); (X.C.-V.); (F.P.)
- Advanced Genomics Laboratory, Program of Hemato-Oncology, Center for Applied Medical Research (CIMA), University of Navarra, 31008 Pamplona, Spain;
| | - Chiara Luongo
- Department of Physiology, Veterinary School, International Excellence Campus for Higher Education and Research (Campus Mare Nostrum), University of Murcia, 30100 Murcia, Spain; (C.L.); (E.R.-T.); (S.N.-S.); (E.P.-O.)
- Institute for Biomedical Research of Murcia, IMIB-Arrixaca, 30100 Murcia, Spain
| | - Ernesto Rodríguez-Tobón
- Department of Physiology, Veterinary School, International Excellence Campus for Higher Education and Research (Campus Mare Nostrum), University of Murcia, 30100 Murcia, Spain; (C.L.); (E.R.-T.); (S.N.-S.); (E.P.-O.)
- Institute for Biomedical Research of Murcia, IMIB-Arrixaca, 30100 Murcia, Spain
| | - Sergio Navarro-Serna
- Department of Physiology, Veterinary School, International Excellence Campus for Higher Education and Research (Campus Mare Nostrum), University of Murcia, 30100 Murcia, Spain; (C.L.); (E.R.-T.); (S.N.-S.); (E.P.-O.)
- Institute for Biomedical Research of Murcia, IMIB-Arrixaca, 30100 Murcia, Spain
| | - Evelyne París-Oller
- Department of Physiology, Veterinary School, International Excellence Campus for Higher Education and Research (Campus Mare Nostrum), University of Murcia, 30100 Murcia, Spain; (C.L.); (E.R.-T.); (S.N.-S.); (E.P.-O.)
- Institute for Biomedical Research of Murcia, IMIB-Arrixaca, 30100 Murcia, Spain
| | | | - Xonia Carvajal-Vergara
- Program of Regenerative Medicine, Centre for Applied Medical Research (CIMA), Instituto de Investigación Sanitaria de Navarra (IdiSNA), University of Navarra, 31008 Pamplona, Spain; (M.M.-J.); (G.C.); (J.R.R.-M.); (G.A.); (P.B.); (A.U.-A.); (X.C.-V.); (F.P.)
| | - Laura Ordovás
- Aragon Agency for Research and Development (ARAID), 50018 Zaragoza, Spain;
- Biomedical Signal Interpretation and Computational Simulation (BSICoS), Institute of Engineering Research (I3A), University of Zaragoza & Instituto de Investigación Sanitaria (IIS), 50018 Zaragoza, Spain
| | - Felipe Prósper
- Program of Regenerative Medicine, Centre for Applied Medical Research (CIMA), Instituto de Investigación Sanitaria de Navarra (IdiSNA), University of Navarra, 31008 Pamplona, Spain; (M.M.-J.); (G.C.); (J.R.R.-M.); (G.A.); (P.B.); (A.U.-A.); (X.C.-V.); (F.P.)
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), 28029 Madrid, Spain
- Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008 Pamplona, Spain
- Department of Hematology and Cell Therapy, Clínica Universidad de Navarra, 31008 Pamplona, Spain
| | - Francisco Alberto García-Vázquez
- Department of Physiology, Veterinary School, International Excellence Campus for Higher Education and Research (Campus Mare Nostrum), University of Murcia, 30100 Murcia, Spain; (C.L.); (E.R.-T.); (S.N.-S.); (E.P.-O.)
- Institute for Biomedical Research of Murcia, IMIB-Arrixaca, 30100 Murcia, Spain
- Correspondence: (F.A.G.-V.); (X.L.A.)
| | - Xabier L. Aranguren
- Program of Regenerative Medicine, Centre for Applied Medical Research (CIMA), Instituto de Investigación Sanitaria de Navarra (IdiSNA), University of Navarra, 31008 Pamplona, Spain; (M.M.-J.); (G.C.); (J.R.R.-M.); (G.A.); (P.B.); (A.U.-A.); (X.C.-V.); (F.P.)
- Correspondence: (F.A.G.-V.); (X.L.A.)
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4
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Ho VW, Grainger DE, Chagraoui H, Porcher C. Specification of the haematopoietic stem cell lineage: From blood-fated mesodermal angioblasts to haemogenic endothelium. Semin Cell Dev Biol 2022; 127:59-67. [PMID: 35125239 DOI: 10.1016/j.semcdb.2022.01.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 01/20/2022] [Accepted: 01/24/2022] [Indexed: 11/19/2022]
Abstract
Haematopoietic stem and progenitor cells emerge from specialized haemogenic endothelial cells in select vascular beds during embryonic development. Specification and commitment to the blood lineage, however, occur before endothelial cells are endowed with haemogenic competence, at the time of mesoderm patterning and production of endothelial cell progenitors (angioblasts). Whilst early blood cell fate specification has long been recognized, very little is known about the mechanisms that induce endothelial cell diversification and progressive acquisition of a blood identity by a subset of these cells. Here, we review the endothelial origin of the haematopoietic system and the complex developmental journey of blood-fated angioblasts. We discuss how recent technological advances will be instrumental to examine the diversity of the embryonic anatomical niches, signaling pathways and downstream epigenetic and transcriptional processes controlling endothelial cell heterogeneity and blood cell fate specification. Ultimately, this will give essential insights into the ontogeny of the cells giving rise to haematopoietic stem cells, that may aid in the development of novel strategies for their in vitro production for clinical purposes.
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Affiliation(s)
- Vivien W Ho
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - David E Grainger
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Hedia Chagraoui
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Catherine Porcher
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, UK.
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5
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Differential Etv2 threshold requirement for endothelial and erythropoietic development. Cell Rep 2022; 39:110881. [PMID: 35649376 PMCID: PMC9203129 DOI: 10.1016/j.celrep.2022.110881] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 02/23/2022] [Accepted: 05/06/2022] [Indexed: 11/21/2022] Open
Abstract
Endothelial and erythropoietic lineages arise from a common developmental progenitor. Etv2 is a master transcriptional regulator required for the development of both lineages. However, the mechanisms through which Etv2 initiates the gene-regulatory networks (GRNs) for endothelial and erythropoietic specification and how the two GRNs diverge downstream of Etv2 remain incompletely understood. Here, by analyzing a hypomorphic Etv2 mutant, we demonstrate different threshold requirements for initiation of the downstream GRNs for endothelial and erythropoietic development. We show that Etv2 functions directly in a coherent feedforward transcriptional network for vascular endothelial development, and a low level of Etv2 expression is sufficient to induce and sustain the endothelial GRN. In contrast, Etv2 induces the erythropoietic GRN indirectly via activation of Tal1, which requires a significantly higher threshold of Etv2 to initiate and sustain erythropoietic development. These results provide important mechanistic insight into the divergence of the endothelial and erythropoietic lineages.
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6
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Zhao H, Choi K. Single cell transcriptome dynamics from pluripotency to FLK1 + mesoderm. Development 2019; 146:dev.182097. [PMID: 31740535 DOI: 10.1242/dev.182097] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 11/11/2019] [Indexed: 12/23/2022]
Abstract
Hemangiogenic progenitors generating blood and endothelial cells are specified from FLK1-expressing (FLK1+) mesoderm by the transcription factor ETV2. FLK1+ mesoderm also contributes to smooth muscle and cardiomyocytes. However, the developmental process of FLK1+ mesoderm generation and its allocation to various cell fates remain obscure. Recent single cell RNA-sequencing studies of early embryos or in vitro-differentiated human embryonic stem (ES) cells have provided unprecedented information on the spatiotemporal resolution of cells in embryogenesis. These snapshots, however, lack information on continuous dynamic developmental processes. Here, we performed single cell RNA sequencing of in vitro-differentiated mouse ES cells to capture the continuous developmental process leading to hemangiogenesis. We found that hemangiogenic progenitors from ES cells develop through intermediate gastrulation stages, which are gradually specified by 'relay'-like highly overlapping transcription factor modules. Moreover, the transcriptional program of the Flk1+ mesoderm was maintained in the smooth muscle lineage, suggesting that smooth muscle is the default fate of Flk1+ mesoderm. We also identified the SRC kinase contributing to ETV2-mediated activation of the hemangiogenic program. This continuous transcriptome map will facilitate both basic and applied studies of mesoderm development.
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Affiliation(s)
- Haiyong Zhao
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Kyunghee Choi
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO 63110, USA
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7
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Menegatti S, de Kruijf M, Garcia‐Alegria E, Lacaud G, Kouskoff V. Transcriptional control of blood cell emergence. FEBS Lett 2019; 593:3304-3315. [PMID: 31432499 PMCID: PMC6916194 DOI: 10.1002/1873-3468.13585] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 08/09/2019] [Accepted: 08/14/2019] [Indexed: 01/06/2023]
Abstract
The haematopoietic system is established during embryonic life through a series of developmental steps that culminates with the generation of haematopoietic stem cells. Characterisation of the transcriptional network that regulates blood cell emergence has led to the identification of transcription factors essential for this process. Among the many factors wired within this complex regulatory network, ETV2, SCL and RUNX1 are the central components. All three factors are absolutely required for blood cell generation, each one controlling a precise step of specification from the mesoderm germ layer to fully functional blood progenitors. Insight into the transcriptional control of blood cell emergence has been used for devising protocols to generate blood cells de novo, either through reprogramming of somatic cells or through forward programming of pluripotent stem cells. Interestingly, the physiological process of blood cell generation and its laboratory-engineered counterpart have very little in common.
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Affiliation(s)
- Sara Menegatti
- Developmental Haematopoiesis GroupFaculty of Biology, Medicine and Healththe University of ManchesterUK
| | - Marcel de Kruijf
- Developmental Haematopoiesis GroupFaculty of Biology, Medicine and Healththe University of ManchesterUK
| | - Eva Garcia‐Alegria
- Developmental Haematopoiesis GroupFaculty of Biology, Medicine and Healththe University of ManchesterUK
| | - Georges Lacaud
- Cancer Research UK Stem Cell Biology GroupCancer Research UK Manchester InstituteThe University of ManchesterMacclesfieldUK
| | - Valerie Kouskoff
- Developmental Haematopoiesis GroupFaculty of Biology, Medicine and Healththe University of ManchesterUK
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9
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Abstract
PURPOSE OF REVIEW Recent studies have established that haematopoietic stem cells (HSCs) remain quiescent in homeostatic conditions, and minimally contribute to haematopoietic homeostasis. However, they undergo extensive cell cycle and expansion upon bone marrow transplantation or haematopoietic injury to reestablish the haematopoietic system. Molecular basis for the HSC activation and expansion is not completely understood. Here, we review the recent study elucidating the role of the developmentally critical Ets transcription factor Etv2 in reestablishing haematopoietic system upon injury through promoting HSC regeneration. RECENT FINDINGS We recently demonstrated that the ETS transcription factor Etv2, a critical factor for haematopoietic and vascular development, is also required for haematopoietic regeneration. Etv2, which is silent in homeostatic HSCs, was transiently activated in regenerating HSPCs and was required for the HSC expansion and regeneration following bone marrow transplantation or haematopoietic injury. As such, while Etv2 is dispensable for maintaining HSCs in steady states, it is required for emergency haematopoiesis. SUMMARY Etv2 has been identified as a novel regulator of haematopoietic regeneration. Comprehensive understanding of the upstream regulators and downstream effectors of Etv2 in haematopoietic regeneration would be critical for fundamental understanding of haematopoietic stem cell biology, and the findings will be broadly applicable to clinical practice involving haematopoietic regenerative medicine; bone marrow transplantation, gene therapy and in-vitro HSC expansion.
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10
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Kang H, Mesquitta WT, Jung HS, Moskvin OV, Thomson JA, Slukvin II. GATA2 Is Dispensable for Specification of Hemogenic Endothelium but Promotes Endothelial-to-Hematopoietic Transition. Stem Cell Reports 2018; 11:197-211. [PMID: 29861167 PMCID: PMC6066910 DOI: 10.1016/j.stemcr.2018.05.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 05/02/2018] [Accepted: 05/03/2018] [Indexed: 01/05/2023] Open
Abstract
The transcriptional factor GATA2 is required for blood and hematopoietic stem cell formation during the hemogenic endothelium (HE) stage of development in the embryo. However, it is unclear if GATA2 controls HE lineage specification or if it solely regulates endothelial-to-hematopoietic transition (EHT). To address this problem, we innovated a unique system, which involved generating GATA2 knockout human embryonic stem cell (hESC) lines with conditional GATA2 expression (iG2-/- hESCs). We demonstrated that GATA2 activity is not required for VE-cadherin+CD43-CD73+ non-HE or VE-cadherin+CD43-CD73- HE generation and subsequent HE diversification into DLL4+ arterial and DLL4- non-arterial lineages. However, GATA2 is primarily needed for HE to undergo EHT. Forced expression of GATA2 in non-HE failed to induce blood formation. The lack of GATA2 requirement for generation of HE and non-HE indicates the critical role of GATA2-independent pathways in specification of these two distinct endothelial lineages.
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Affiliation(s)
- HyunJun Kang
- Wisconsin National Primate Research Center, University of Wisconsin Graduate School, 1220 Capitol Court, Madison, WI 53715, USA
| | - Walatta-Tseyon Mesquitta
- Wisconsin National Primate Research Center, University of Wisconsin Graduate School, 1220 Capitol Court, Madison, WI 53715, USA
| | - Ho Sun Jung
- Wisconsin National Primate Research Center, University of Wisconsin Graduate School, 1220 Capitol Court, Madison, WI 53715, USA
| | - Oleg V Moskvin
- Wisconsin National Primate Research Center, University of Wisconsin Graduate School, 1220 Capitol Court, Madison, WI 53715, USA
| | - James A Thomson
- Morgridge Institute for Research, 330 N. Orchard Street, Madison, WI 53715, USA; Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison, WI 53707-7365, USA; Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, CA 93106, USA
| | - Igor I Slukvin
- Wisconsin National Primate Research Center, University of Wisconsin Graduate School, 1220 Capitol Court, Madison, WI 53715, USA; Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison, WI 53707-7365, USA; Department of Pathology and Laboratory Medicine, University of Wisconsin Medical School, 600 Highland Avenue, Madison, WI 53792, USA.
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11
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Koyano-Nakagawa N, Garry DJ. Etv2 as an essential regulator of mesodermal lineage development. Cardiovasc Res 2018; 113:1294-1306. [PMID: 28859300 DOI: 10.1093/cvr/cvx133] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 07/24/2017] [Indexed: 11/14/2022] Open
Abstract
The 'master regulatory factors' that position at the top of the genetic hierarchy of lineage determination have been a focus of intense interest, and have been investigated in various systems. Etv2/Etsrp71/ER71 is such a factor that is both necessary and sufficient for the development of haematopoietic and endothelial lineages. As such, genetic ablation of Etv2 leads to complete loss of blood and vessels, and overexpression can convert non-endothelial cells to the endothelial lineage. Understanding such master regulatory role of a lineage is not only a fundamental quest in developmental biology, but also holds immense possibilities in regenerative medicine. To harness its activity and utility for therapeutic interventions, it is essential to understand the regulatory mechanisms, molecular function, and networks that surround Etv2. In this review, we provide a comprehensive overview of Etv2 biology focused on mouse and human systems.
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Affiliation(s)
- Naoko Koyano-Nakagawa
- Lillehei Heart Institute, Department of Medicine, University of Minnesota, 2231 6th st. SE, Minneapolis, MN 55455, USA
| | - Daniel J Garry
- Lillehei Heart Institute, Department of Medicine, University of Minnesota, 2231 6th st. SE, Minneapolis, MN 55455, USA
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12
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Kabir AU, Lee TJ, Pan H, Berry JC, Krchma K, Wu J, Liu F, Kang HK, Hinman K, Yang L, Hamilton S, Zhou Q, Veis DJ, Mecham RP, Wickline SA, Miller MJ, Choi K. Requisite endothelial reactivation and effective siRNA nanoparticle targeting of Etv2/Er71 in tumor angiogenesis. JCI Insight 2018; 3:97349. [PMID: 29669933 DOI: 10.1172/jci.insight.97349] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 03/20/2018] [Indexed: 01/24/2023] Open
Abstract
Angiogenesis, new blood vessel formation from preexisting vessels, is critical for solid tumor growth. As such, there have been efforts to inhibit angiogenesis as a means to obstruct tumor growth. However, antiangiogenic therapy faces major challenges to the selective targeting of tumor-associated-vessels, as current antiangiogenic targets also disrupt steady-state vessels. Here, we demonstrate that the developmentally critical transcription factor Etv2 is selectively upregulated in both human and mouse tumor-associated endothelial cells (TAECs) and is required for tumor angiogenesis. Two-photon imaging revealed that Etv2-deficient tumor-associated vasculature remained similar to that of steady-state vessels. Etv2-deficient TAECs displayed decreased Flk1 (also known as Vegfr2) expression, FLK1 activation, and proliferation. Endothelial tube formation, proliferation, and sprouting response to VEGF, but not to FGF2, was reduced in Etv2-deficient ECs. ROS activated Etv2 expression in ECs, and ROS blockade inhibited Etv2 expression in TAECs in vivo. Systemic administration of Etv2 siRNA nanoparticles potently inhibited tumor growth and angiogenesis without cardiovascular side effects. These studies highlight a link among vascular oxidative stress, Etv2 expression, and VEGF response that is critical for tumor angiogenesis. Targeting the ETV2 pathway might offer a unique opportunity for more selective antiangiogenic therapies.
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Affiliation(s)
- Ashraf Ul Kabir
- Department of Pathology and Immunology and.,Molecular and Cell Biology Program, Washington University School of Medicine, St. Louis, Missouri, USA
| | | | - Hua Pan
- Health Heart Institute, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Jeffrey C Berry
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | | | - Jun Wu
- Department of Pathology and Immunology and
| | - Fang Liu
- Department of Pathology and Immunology and
| | - Hee-Kyoung Kang
- Department of Pharmacology, School of Medicine, Jeju National University, Jeju, South Korea
| | - Kristina Hinman
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Lihua Yang
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Samantha Hamilton
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Qingyu Zhou
- Department of Pharmaceutical Science, College of Pharmacy, University of South Florida, Tampa, Florida, USA
| | - Deborah J Veis
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Robert P Mecham
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Samuel A Wickline
- Health Heart Institute, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Mark J Miller
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Kyunghee Choi
- Department of Pathology and Immunology and.,Molecular and Cell Biology Program, Washington University School of Medicine, St. Louis, Missouri, USA.,Graduate School of Biotechnology, Kyung Hee University, Yongin, South Korea
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13
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Teichweyde N, Kasperidus L, Carotta S, Kouskoff V, Lacaud G, Horn PA, Heinrichs S, Klump H. HOXB4 Promotes Hemogenic Endothelium Formation without Perturbing Endothelial Cell Development. Stem Cell Reports 2018; 10:875-889. [PMID: 29456178 PMCID: PMC5919293 DOI: 10.1016/j.stemcr.2018.01.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 01/15/2018] [Accepted: 01/16/2018] [Indexed: 12/25/2022] Open
Abstract
Generation of hematopoietic stem cells (HSCs) from pluripotent stem cells, in vitro, holds great promise for regenerative therapies. Primarily, this has been achieved in mouse cells by overexpression of the homeotic selector protein HOXB4. The exact cellular stage at which HOXB4 promotes hematopoietic development, in vitro, is not yet known. However, its identification is a prerequisite to unambiguously identify the molecular circuits controlling hematopoiesis, since the activity of HOX proteins is highly cell and context dependent. To identify that stage, we retrovirally expressed HOXB4 in differentiating mouse embryonic stem cells (ESCs). Through the use of Runx1(-/-) ESCs containing a doxycycline-inducible Runx1 coding sequence, we uncovered that HOXB4 promoted the formation of hemogenic endothelium cells without altering endothelial cell development. Whole-transcriptome analysis revealed that its expression mediated the upregulation of transcription of core transcription factors necessary for hematopoiesis, culminating in the formation of blood progenitors upon initiation of Runx1 expression.
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Affiliation(s)
- Nadine Teichweyde
- Institute for Transfusion Medicine, University Hospital Essen, Virchowstraße 179, 45147 Essen, Germany
| | - Lara Kasperidus
- Institute for Transfusion Medicine, University Hospital Essen, Virchowstraße 179, 45147 Essen, Germany; Department of Bone Marrow Transplantation, University Hospital Essen, Hufelandstraße 55, 45147 Essen, Germany
| | - Sebastian Carotta
- Cancer Cell Signaling, Boehringer Ingelheim RCV, Dr Boehringer-Gasse, 1120 Vienna, Austria
| | - Valerie Kouskoff
- Cancer Research UK Stem Cell Haematopoiesis Group, Cancer Research UK Manchester Institute, The University of Manchester, Wilmslow Road, Manchester M20 4BX, UK
| | - Georges Lacaud
- Cancer Research UK Stem Cell Biology Group, Cancer Research UK Manchester Institute, The University of Manchester, Wilmslow Road, Manchester M20 4BX, UK
| | - Peter A Horn
- Institute for Transfusion Medicine, University Hospital Essen, Virchowstraße 179, 45147 Essen, Germany
| | - Stefan Heinrichs
- Institute for Transfusion Medicine, University Hospital Essen, Virchowstraße 179, 45147 Essen, Germany
| | - Hannes Klump
- Institute for Transfusion Medicine, University Hospital Essen, Virchowstraße 179, 45147 Essen, Germany.
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14
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Stanulovic VS, Cauchy P, Assi SA, Hoogenkamp M. LMO2 is required for TAL1 DNA binding activity and initiation of definitive haematopoiesis at the haemangioblast stage. Nucleic Acids Res 2017; 45:9874-9888. [PMID: 28973433 PMCID: PMC5622341 DOI: 10.1093/nar/gkx573] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 06/27/2017] [Indexed: 02/06/2023] Open
Abstract
LMO2 is a bridging factor within a DNA binding complex and is required for definitive haematopoiesis to occur. The developmental stage of the block in haematopoietic specification is not known. We show that Lmo2−/− mouse embryonic stem cells differentiated to Flk-1+ haemangioblasts, but less efficiently to haemogenic endothelium, which only produced primitive haematopoietic progenitors. Genome-wide approaches indicated that LMO2 is required at the haemangioblast stage to position the TAL1/LMO2/LDB1 complex to regulatory elements that are important for the establishment of the haematopoietic developmental program. In the absence of LMO2, the target site recognition of TAL1 is impaired. The lack of LMO2 resulted in altered gene expression levels already at the haemangioblast stage, with transcription factor genes accounting for ∼15% of affected genes. Comparison of Lmo2−/− with Tal1−/− Flk-1+ cells further showed that TAL1 was required to initiate or sustain Lmo2 expression.
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Affiliation(s)
- Vesna S Stanulovic
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Pierre Cauchy
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Salam A Assi
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Maarten Hoogenkamp
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
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15
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The Ets2 Repressor Factor (Erf) Is Required for Effective Primitive and Definitive Hematopoiesis. Mol Cell Biol 2017; 37:MCB.00183-17. [PMID: 28694332 DOI: 10.1128/mcb.00183-17] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 06/19/2017] [Indexed: 01/09/2023] Open
Abstract
Erf is a gene for a ubiquitously expressed Ets DNA-binding domain-containing transcriptional repressor. Erf haploinsufficiency causes craniosynostosis in humans and mice, while its absence in mice leads to failed chorioallantoic fusion and death at embryonic day 10.5 (E10.5). In this study, we show that Erf is required in all three waves of embryonic hematopoiesis. Mice lacking Erf in the embryo proper exhibited severe anemia and died around embryonic day 14.5. Erf epiblast-specific knockout embryos had reduced numbers of circulating blood cells from E9.5 onwards, with the development of severe anemia by E14.5. Elimination of Erf resulted in both reduced and more immature primitive erythroblasts at E9.5 to E10.5. Reduced definitive erythroid colony-forming activity was found in the bloodstream of E10.5 embryos and in the fetal liver at E11.5 to E13.5. Finally, elimination of Erf resulted in impaired repopulation ability, indicating that Erf is necessary for hematopoietic stem cell maintenance or differentiation. We conclude that Erf is required for both primitive and erythromyeloid progenitor waves of hematopoietic stem cell (HSC)-independent hematopoiesis as well as for the normal function of HSCs.
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16
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Xu CX, Lee TJ, Sakurai N, Krchma K, Liu F, Li D, Wang T, Choi K. ETV2/ER71 regulates hematopoietic regeneration by promoting hematopoietic stem cell proliferation. J Exp Med 2017; 214:1643-1653. [PMID: 28461595 PMCID: PMC5460995 DOI: 10.1084/jem.20160923] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 02/13/2017] [Accepted: 03/20/2017] [Indexed: 01/28/2023] Open
Abstract
Xu et al. show that Etv2 is required for hematopoietic stem and progenitor cell (HSPC) proliferation and expansion after bone marrow transplantation and hematopoietic injury. c-Kit functions downstream of Etv2 in mediating HSPC proliferation and expansion. Recent studies have established that hematopoietic stem cells (HSCs) are quiescent in homeostatic conditions but undergo extensive cell cycle and expansion upon bone marrow (BM) transplantation or hematopoietic injury. The molecular basis for HSC activation and expansion is not completely understood. In this study, we found that key developmentally critical genes controlling hematopoietic stem and progenitor cell (HSPC) generation were up-regulated in HSPCs upon hematopoietic injury. In particular, we found that the ETS transcription factor Ets variant 2 (Etv2; also known as Er71) was up-regulated by reactive oxygen species in HSPCs and was necessary in a cell-autonomous manner for HSPC expansion and regeneration after BM transplantation and hematopoietic injury. We found c-Kit to be downstream of ETV2. As such, lentiviral c-Kit expression rescued Etv2-deficient HSPC proliferation defects in vitro and in short-term BM transplantation in vivo. These findings demonstrate that Etv2 is an important regulator of hematopoietic regeneration.
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Affiliation(s)
- Can-Xin Xu
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110.,The People's Hospital of Hunan Province and Hunan Normal University Institute for Clinical and Translational Science, Changsha, Hunan 410006, China
| | - Tae-Jin Lee
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110
| | - Nagisa Sakurai
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110
| | - Karen Krchma
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110
| | - Fang Liu
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110
| | - Daofeng Li
- Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110
| | - Ting Wang
- Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110
| | - Kyunghee Choi
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110 .,Developmental, Regenerative, and Stem Cell Biology Program, Washington University School of Medicine, St. Louis, MO 63110
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17
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SCL/TAL1: a multifaceted regulator from blood development to disease. Blood 2017; 129:2051-2060. [DOI: 10.1182/blood-2016-12-754051] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 01/17/2017] [Indexed: 12/12/2022] Open
Abstract
Abstract
SCL/TAL1 (stem cell leukemia/T-cell acute lymphoblastic leukemia [T-ALL] 1) is an essential transcription factor in normal and malignant hematopoiesis. It is required for specification of the blood program during development, adult hematopoietic stem cell survival and quiescence, and terminal maturation of select blood lineages. Following ectopic expression, SCL contributes to oncogenesis in T-ALL. Remarkably, SCL’s activities are all mediated through nucleation of a core quaternary protein complex (SCL:E-protein:LMO1/2 [LIM domain only 1 or 2]:LDB1 [LIM domain-binding protein 1]) and dynamic recruitment of conserved combinatorial associations of additional regulators in a lineage- and stage-specific context. The finely tuned control of SCL’s regulatory functions (lineage priming, activation, and repression of gene expression programs) provides insight into fundamental developmental and transcriptional mechanisms, and highlights mechanistic parallels between normal and oncogenic processes. Importantly, recent discoveries are paving the way to the development of innovative therapeutic opportunities in SCL+ T-ALL.
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18
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Zhao H, Xu C, Lee TJ, Liu F, Choi K. ETS transcription factor ETV2/ER71/Etsrp in hematopoietic and vascular development, injury, and regeneration. Dev Dyn 2017; 246:318-327. [DOI: 10.1002/dvdy.24483] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 12/13/2016] [Accepted: 12/13/2016] [Indexed: 12/17/2022] Open
Affiliation(s)
- Haiyong Zhao
- Department of Pathology and Immunology; Washington University School of Medicine; St. Louis Missouri
| | - Canxin Xu
- Department of Pathology and Immunology; Washington University School of Medicine; St. Louis Missouri
| | - Tae-Jin Lee
- Department of Pathology and Immunology; Washington University School of Medicine; St. Louis Missouri
| | - Fang Liu
- Department of Pathology and Immunology; Washington University School of Medicine; St. Louis Missouri
| | - Kyunghee Choi
- Department of Pathology and Immunology; Washington University School of Medicine; St. Louis Missouri
- Developmental; Regenerative, and Stem Cell Biology Program, Washington University School of Medicine; St. Louis Missouri
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19
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Garcia-Alegria E, Menegatti S, Batta K, Cuvertino S, Florkowska M, Kouskoff V. Emerging concepts for the in vitro derivation of murine haematopoietic stem and progenitor cells. FEBS Lett 2016; 590:4116-4125. [PMID: 27404333 DOI: 10.1002/1873-3468.12300] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 07/04/2016] [Accepted: 07/09/2016] [Indexed: 02/11/2024]
Abstract
Well into the second decade of the 21st century, the field of regenerative medicine is bursting with hopes and promises to heal young and old. The bespoken generation of cells is thought to offer unprecedented cures for a vast range of diseases. Haematological disorders have already benefited tremendously from stem cell therapy in the form of bone marrow transplantation. However, lack of compatible donors often means that patients remain on transplantation waiting lists for too long. The in vitro derivation of haematopoietic stem cells offers the possibility to generate tailor-made cells for the treatment of these patients. Promising approaches to generate in vitro-derived blood progenitors include the directed differentiation of pluripotent stem cells and the reprogramming of somatic cells.
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Affiliation(s)
- Eva Garcia-Alegria
- Cancer Research UK Stem Cell Haematopoiesis Group, Cancer Research UK Manchester Institute, The University of Manchester, UK
| | - Sara Menegatti
- Cancer Research UK Stem Cell Haematopoiesis Group, Cancer Research UK Manchester Institute, The University of Manchester, UK
| | - Kiran Batta
- Cancer Research UK Stem Cell Biology Group, Cancer Research UK Manchester Institute, The University of Manchester, UK
| | - Sara Cuvertino
- Cancer Research UK Stem Cell Haematopoiesis Group, Cancer Research UK Manchester Institute, The University of Manchester, UK
| | - Magdalena Florkowska
- Cancer Research UK Stem Cell Biology Group, Cancer Research UK Manchester Institute, The University of Manchester, UK
| | - Valerie Kouskoff
- Cancer Research UK Stem Cell Haematopoiesis Group, Cancer Research UK Manchester Institute, The University of Manchester, UK
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20
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Nasrallah R, Fast EM, Solaimani P, Knezevic K, Eliades A, Patel R, Thambyrajah R, Unnikrishnan A, Thoms J, Beck D, Vink CS, Smith A, Wong J, Shepherd M, Kent D, Roychoudhuri R, Paul F, Klippert J, Hammes A, Willnow T, Göttgens B, Dzierzak E, Zon LI, Lacaud G, Kouskoff V, Pimanda JE. Identification of novel regulators of developmental hematopoiesis using Endoglin regulatory elements as molecular probes. Blood 2016; 128:1928-1939. [PMID: 27554085 PMCID: PMC5064716 DOI: 10.1182/blood-2016-02-697870] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 08/15/2016] [Indexed: 12/13/2022] Open
Abstract
Enhancers are the primary determinants of cell identity, and specific promoter/enhancer combinations of Endoglin (ENG) have been shown to target blood and endothelium in the embryo. Here, we generated a series of embryonic stem cell lines, each targeted with reporter constructs driven by specific promoter/enhancer combinations of ENG, to evaluate their discriminative potential and value as molecular probes of the corresponding transcriptome. The Eng promoter (P) in combination with the -8/+7/+9-kb enhancers, targeted cells in FLK1 mesoderm that were enriched for blast colony forming potential, whereas the P/-8-kb enhancer targeted TIE2+/c-KIT+/CD41- endothelial cells that were enriched for hematopoietic potential. These fractions were isolated using reporter expression and their transcriptomes profiled by RNA-seq. There was high concordance between our signatures and those from embryos with defects at corresponding stages of hematopoiesis. Of the 6 genes that were upregulated in both hemogenic mesoderm and hemogenic endothelial fractions targeted by the reporters, LRP2, a multiligand receptor, was the only gene that had not previously been associated with hematopoiesis. We show that LRP2 is indeed involved in definitive hematopoiesis and by doing so validate the use of reporter gene-coupled enhancers as probes to gain insights into transcriptional changes that facilitate cell fate transitions.
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Affiliation(s)
- Rabab Nasrallah
- Lowy Cancer Research Centre and the Prince of Wales Clinical School, University of New South Wales Australia, Sydney, Australia
| | - Eva M Fast
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA; Howard Hughes Medical Institute, Stem Cell Program and Division of Pediatric Hematology/Oncology, Boston Children's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
| | - Parham Solaimani
- Erasmus Medical Center Stem Cell Institute, Department of Cell Biology, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Kathy Knezevic
- Lowy Cancer Research Centre and the Prince of Wales Clinical School, University of New South Wales Australia, Sydney, Australia
| | - Alexia Eliades
- Cancer Research United Kingdom Manchester Institute, The University of Manchester, Manchester, United Kingdom
| | - Rahima Patel
- Cancer Research United Kingdom Manchester Institute, The University of Manchester, Manchester, United Kingdom
| | - Roshana Thambyrajah
- Cancer Research United Kingdom Manchester Institute, The University of Manchester, Manchester, United Kingdom
| | - Ashwin Unnikrishnan
- Lowy Cancer Research Centre and the Prince of Wales Clinical School, University of New South Wales Australia, Sydney, Australia
| | - Julie Thoms
- Lowy Cancer Research Centre and the Prince of Wales Clinical School, University of New South Wales Australia, Sydney, Australia
| | - Dominik Beck
- Lowy Cancer Research Centre and the Prince of Wales Clinical School, University of New South Wales Australia, Sydney, Australia
| | - Chris S Vink
- Erasmus Medical Center Stem Cell Institute, Department of Cell Biology, Erasmus University Medical Center, Rotterdam, The Netherlands; Medical Research Council Centre for Inflammation Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Aileen Smith
- Department of Haematology, Wellcome Trust and Medical Research Council Cambridge Stem Cell Institute and Cambridge Institute for Medical Research, Cambridge University, Cambridge, United Kingdom
| | - Jason Wong
- Lowy Cancer Research Centre and the Prince of Wales Clinical School, University of New South Wales Australia, Sydney, Australia
| | - Mairi Shepherd
- Department of Haematology, Wellcome Trust and Medical Research Council Cambridge Stem Cell Institute and Cambridge Institute for Medical Research, Cambridge University, Cambridge, United Kingdom
| | - David Kent
- Department of Haematology, Wellcome Trust and Medical Research Council Cambridge Stem Cell Institute and Cambridge Institute for Medical Research, Cambridge University, Cambridge, United Kingdom
| | - Rahul Roychoudhuri
- The Babraham Institute, Babraham Research Campus, Cambridge, United Kingdom
| | - Fabian Paul
- Max Delbrueck Center for Molecular Medicine, Berlin, Germany; and
| | - Julia Klippert
- Max Delbrueck Center for Molecular Medicine, Berlin, Germany; and
| | - Annette Hammes
- Max Delbrueck Center for Molecular Medicine, Berlin, Germany; and
| | - Thomas Willnow
- Max Delbrueck Center for Molecular Medicine, Berlin, Germany; and
| | - Bertie Göttgens
- Department of Haematology, Wellcome Trust and Medical Research Council Cambridge Stem Cell Institute and Cambridge Institute for Medical Research, Cambridge University, Cambridge, United Kingdom
| | - Elaine Dzierzak
- Erasmus Medical Center Stem Cell Institute, Department of Cell Biology, Erasmus University Medical Center, Rotterdam, The Netherlands; Medical Research Council Centre for Inflammation Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Leonard I Zon
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA; Howard Hughes Medical Institute, Stem Cell Program and Division of Pediatric Hematology/Oncology, Boston Children's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
| | - George Lacaud
- Cancer Research United Kingdom Manchester Institute, The University of Manchester, Manchester, United Kingdom
| | - Valerie Kouskoff
- Cancer Research United Kingdom Manchester Institute, The University of Manchester, Manchester, United Kingdom
| | - John E Pimanda
- Lowy Cancer Research Centre and the Prince of Wales Clinical School, University of New South Wales Australia, Sydney, Australia; Department of Haematology, The Prince of Wales Hospital, Sydney, Australia
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21
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Thambyrajah R, Patel R, Mazan M, Lie-a-Ling M, Lilly A, Eliades A, Menegatti S, Garcia-Alegria E, Florkowska M, Batta K, Kouskoff V, Lacaud G. New insights into the regulation by RUNX1 and GFI1(s) proteins of the endothelial to hematopoietic transition generating primordial hematopoietic cells. Cell Cycle 2016; 15:2108-2114. [PMID: 27399214 PMCID: PMC4993433 DOI: 10.1080/15384101.2016.1203491] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 06/07/2016] [Accepted: 06/09/2016] [Indexed: 10/26/2022] Open
Abstract
The first hematopoietic cells are generated very early in ontogeny to support the growth of the embryo and to provide the foundation to the adult hematopoietic system. There is a considerable therapeutic interest in understanding how these first blood cells are generated in order to try to reproduce this process in vitro. This would allow generating blood products, or hematopoietic cell populations from embryonic stem (ES) cells, induced pluripotent stem cells or through directed reprogramming. Recent studies have clearly established that the first hematopoietic cells originate from a hemogenic endothelium (HE) through an endothelial to hematopoietic transition (EHT). The molecular mechanisms underlining this transition remain largely unknown with the exception that the transcription factor RUNX1 is critical for this process. In this Extra Views report, we discuss our recent studies demonstrating that the transcriptional repressors GFI1 and GFI1B have a critical role in the EHT. We established that these RUNX1 transcriptional targets are actively implicated in the downregulation of the endothelial program and the loss of endothelial identity during the formation of the first blood cells. In addition, our results suggest that GFI1 expression provides an ideal novel marker to identify, isolate and study the HE cell population.
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Affiliation(s)
- Roshana Thambyrajah
- CRUK Stem Cell Biology, Cancer Research UK Manchester Institute, Manchester, UK
| | - Rahima Patel
- CRUK Stem Cell Biology, Cancer Research UK Manchester Institute, Manchester, UK
| | - Milena Mazan
- CRUK Stem Cell Biology, Cancer Research UK Manchester Institute, Manchester, UK
| | - Michael Lie-a-Ling
- CRUK Stem Cell Biology, Cancer Research UK Manchester Institute, Manchester, UK
| | - Andrew Lilly
- CRUK Stem Cell Haematopoiesis, Cancer Research UK Manchester Institute, Manchester, UK
| | - Alexia Eliades
- CRUK Stem Cell Haematopoiesis, Cancer Research UK Manchester Institute, Manchester, UK
| | - Sara Menegatti
- CRUK Stem Cell Haematopoiesis, Cancer Research UK Manchester Institute, Manchester, UK
| | - Eva Garcia-Alegria
- CRUK Stem Cell Haematopoiesis, Cancer Research UK Manchester Institute, Manchester, UK
| | | | - Kiran Batta
- CRUK Stem Cell Biology, Cancer Research UK Manchester Institute, Manchester, UK
| | - Valerie Kouskoff
- CRUK Stem Cell Haematopoiesis, Cancer Research UK Manchester Institute, Manchester, UK
| | - Georges Lacaud
- CRUK Stem Cell Biology, Cancer Research UK Manchester Institute, Manchester, UK
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22
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Eliades A, Wareing S, Marinopoulou E, Fadlullah MZH, Patel R, Grabarek JB, Plusa B, Lacaud G, Kouskoff V. The Hemogenic Competence of Endothelial Progenitors Is Restricted by Runx1 Silencing during Embryonic Development. Cell Rep 2016; 15:2185-2199. [PMID: 27239041 PMCID: PMC4906370 DOI: 10.1016/j.celrep.2016.05.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 03/24/2016] [Accepted: 04/27/2016] [Indexed: 01/08/2023] Open
Abstract
It is now well-established that hematopoietic stem cells (HSCs) and progenitor cells originate from a specialized subset of endothelium, termed hemogenic endothelium (HE), via an endothelial-to-hematopoietic transition. However, the molecular mechanisms determining which endothelial progenitors possess this hemogenic potential are currently unknown. Here, we investigated the changes in hemogenic potential in endothelial progenitors at the early stages of embryonic development. Using an ETV2::GFP reporter mouse to isolate emerging endothelial progenitors, we observed a dramatic decrease in hemogenic potential between embryonic day (E)7.5 and E8.5. At the molecular level, Runx1 is expressed at much lower levels in E8.5 intra-embryonic progenitors, while Bmi1 expression is increased. Remarkably, the ectopic expression of Runx1 in these progenitors fully restores their hemogenic potential, as does the suppression of BMI1 function. Altogether, our data demonstrate that hemogenic competency in recently specified endothelial progenitors is restrained through the active silencing of Runx1 expression.
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Affiliation(s)
- Alexia Eliades
- Cancer Research UK Stem Cell Hematopoiesis Group, Cancer Research UK Manchester Institute, The University of Manchester, Manchester M20 4BX, UK
| | - Sarah Wareing
- Cancer Research UK Stem Cell Hematopoiesis Group, Cancer Research UK Manchester Institute, The University of Manchester, Manchester M20 4BX, UK
| | - Elli Marinopoulou
- Cancer Research UK Stem Cell Biology Group, Cancer Research UK Manchester Institute, The University of Manchester, Manchester M20 4BX, UK
| | - Muhammad Z H Fadlullah
- Cancer Research UK Stem Cell Hematopoiesis Group, Cancer Research UK Manchester Institute, The University of Manchester, Manchester M20 4BX, UK
| | - Rahima Patel
- Cancer Research UK Stem Cell Biology Group, Cancer Research UK Manchester Institute, The University of Manchester, Manchester M20 4BX, UK
| | - Joanna B Grabarek
- Faculty of Life Sciences, The University of Manchester, Manchester M13 9PT, UK
| | - Berenika Plusa
- Faculty of Life Sciences, The University of Manchester, Manchester M13 9PT, UK
| | - Georges Lacaud
- Cancer Research UK Stem Cell Biology Group, Cancer Research UK Manchester Institute, The University of Manchester, Manchester M20 4BX, UK.
| | - Valerie Kouskoff
- Cancer Research UK Stem Cell Hematopoiesis Group, Cancer Research UK Manchester Institute, The University of Manchester, Manchester M20 4BX, UK.
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23
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Shah AV, Birdsey GM, Randi AM. Regulation of endothelial homeostasis, vascular development and angiogenesis by the transcription factor ERG. Vascul Pharmacol 2016; 86:3-13. [PMID: 27208692 PMCID: PMC5404112 DOI: 10.1016/j.vph.2016.05.003] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 04/08/2016] [Accepted: 05/16/2016] [Indexed: 01/06/2023]
Abstract
Over the last few years, the ETS transcription factor ERG has emerged as a major regulator of endothelial function. Multiple studies have shown that ERG plays a crucial role in promoting angiogenesis and vascular stability during development and after birth. In the mature vasculature ERG also functions to maintain endothelial homeostasis, by transactivating genes involved in key endothelial functions, while repressing expression of pro-inflammatory genes. Its homeostatic role is lineage-specific, since ectopic expression of ERG in non-endothelial tissues such as prostate is detrimental and contributes to oncogenesis. This review summarises the main roles and pathways controlled by ERG in the vascular endothelium, its transcriptional targets and its functional partners and the emerging evidence on the pathways regulating ERG's activity and expression.
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Affiliation(s)
- Aarti V Shah
- Vascular Sciences, Imperial Centre for Translational and Experimental Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Graeme M Birdsey
- Vascular Sciences, Imperial Centre for Translational and Experimental Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Anna M Randi
- Vascular Sciences, Imperial Centre for Translational and Experimental Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom.
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24
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Craig MP, Sumanas S. ETS transcription factors in embryonic vascular development. Angiogenesis 2016; 19:275-85. [PMID: 27126901 DOI: 10.1007/s10456-016-9511-z] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 04/19/2016] [Indexed: 11/25/2022]
Abstract
At least thirteen ETS-domain transcription factors are expressed during embryonic hematopoietic or vascular development and potentially function in the formation and maintenance of the embryonic vasculature or blood lineages. This review summarizes our current understanding of the specific roles played by ETS factors in vasculogenesis and angiogenesis and the implications of functional redundancies between them.
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Affiliation(s)
- Michael P Craig
- Department of Biochemistry and Molecular Biology, Wright State University, 3640 Colonel Glenn Hwy., Dayton, OH, 45435, USA.,Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH, 45229, USA
| | - Saulius Sumanas
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH, 45229, USA.
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25
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Goode DK, Obier N, Vijayabaskar MS, Lie-A-Ling M, Lilly AJ, Hannah R, Lichtinger M, Batta K, Florkowska M, Patel R, Challinor M, Wallace K, Gilmour J, Assi SA, Cauchy P, Hoogenkamp M, Westhead DR, Lacaud G, Kouskoff V, Göttgens B, Bonifer C. Dynamic Gene Regulatory Networks Drive Hematopoietic Specification and Differentiation. Dev Cell 2016; 36:572-87. [PMID: 26923725 PMCID: PMC4780867 DOI: 10.1016/j.devcel.2016.01.024] [Citation(s) in RCA: 166] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 12/04/2015] [Accepted: 01/26/2016] [Indexed: 12/22/2022]
Abstract
Metazoan development involves the successive activation and silencing of specific gene expression programs and is driven by tissue-specific transcription factors programming the chromatin landscape. To understand how this process executes an entire developmental pathway, we generated global gene expression, chromatin accessibility, histone modification, and transcription factor binding data from purified embryonic stem cell-derived cells representing six sequential stages of hematopoietic specification and differentiation. Our data reveal the nature of regulatory elements driving differential gene expression and inform how transcription factor binding impacts on promoter activity. We present a dynamic core regulatory network model for hematopoietic specification and demonstrate its utility for the design of reprogramming experiments. Functional studies motivated by our genome-wide data uncovered a stage-specific role for TEAD/YAP factors in mammalian hematopoietic specification. Our study presents a powerful resource for studying hematopoiesis and demonstrates how such data advance our understanding of mammalian development.
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Affiliation(s)
- Debbie K Goode
- Department of Haematology, Cambridge Institute for Medical Research and Wellcome Trust and MRC Cambridge Stem Cell Institute, Cambridge CB2 0XY, UK
| | - Nadine Obier
- Institute of Cancer end Genomic Sciences, College of Medicine and Dentistry, University of Birmingham, Birmingham B152TT, UK
| | - M S Vijayabaskar
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Michael Lie-A-Ling
- CRUK Manchester Institute, University of Manchester, Manchester M20 4BX, UK
| | - Andrew J Lilly
- CRUK Manchester Institute, University of Manchester, Manchester M20 4BX, UK
| | - Rebecca Hannah
- Department of Haematology, Cambridge Institute for Medical Research and Wellcome Trust and MRC Cambridge Stem Cell Institute, Cambridge CB2 0XY, UK
| | - Monika Lichtinger
- Institute of Cancer end Genomic Sciences, College of Medicine and Dentistry, University of Birmingham, Birmingham B152TT, UK
| | - Kiran Batta
- CRUK Manchester Institute, University of Manchester, Manchester M20 4BX, UK
| | | | - Rahima Patel
- CRUK Manchester Institute, University of Manchester, Manchester M20 4BX, UK
| | - Mairi Challinor
- CRUK Manchester Institute, University of Manchester, Manchester M20 4BX, UK
| | - Kirstie Wallace
- CRUK Manchester Institute, University of Manchester, Manchester M20 4BX, UK
| | - Jane Gilmour
- Institute of Cancer end Genomic Sciences, College of Medicine and Dentistry, University of Birmingham, Birmingham B152TT, UK
| | - Salam A Assi
- Institute of Cancer end Genomic Sciences, College of Medicine and Dentistry, University of Birmingham, Birmingham B152TT, UK
| | - Pierre Cauchy
- Institute of Cancer end Genomic Sciences, College of Medicine and Dentistry, University of Birmingham, Birmingham B152TT, UK
| | - Maarten Hoogenkamp
- Institute of Cancer end Genomic Sciences, College of Medicine and Dentistry, University of Birmingham, Birmingham B152TT, UK
| | - David R Westhead
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Georges Lacaud
- CRUK Manchester Institute, University of Manchester, Manchester M20 4BX, UK
| | - Valerie Kouskoff
- CRUK Manchester Institute, University of Manchester, Manchester M20 4BX, UK
| | - Berthold Göttgens
- Department of Haematology, Cambridge Institute for Medical Research and Wellcome Trust and MRC Cambridge Stem Cell Institute, Cambridge CB2 0XY, UK
| | - Constanze Bonifer
- Institute of Cancer end Genomic Sciences, College of Medicine and Dentistry, University of Birmingham, Birmingham B152TT, UK.
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26
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Abstract
SCL, a transcription factor of the basic helix-loop-helix family, is a master regulator of hematopoiesis. Scl specifies lateral plate mesoderm to a hematopoietic fate and establishes boundaries by inhibiting the cardiac lineage. A combinatorial interaction between Scl and Vegfa/Flk1 sets in motion the first wave of primitive hematopoiesis. Subsequently, definitive hematopoietic stem cells (HSCs) emerge from the embryo proper via an endothelial-to-hematopoietic transition controlled by Runx1, acting with Scl and Gata2. Past this stage, Scl in steady state HSCs is redundant with Lyl1, a highly homologous factor. However, Scl is haploinsufficient in stress response, when a rare subpopulation of HSCs with very long term repopulating capacity is called into action. SCL activates transcription by recruiting a core complex on DNA that necessarily includes E2A/HEB, GATA1-3, LIM-only proteins LMO1/2, LDB1, and an extended complex comprising ETO2, RUNX1, ERG, or FLI1. These interactions confer multifunctionality to a complex that can control cell proliferation in erythroid progenitors or commitment to terminal differentiation through variations in single component. Ectopic SCL and LMO1/2 expression in immature thymocytes activates of a stem cell gene network and reprogram cells with a finite lifespan into self-renewing preleukemic stem cells (pre-LSCs), an initiating event in T-cell acute lymphoblastic leukemias. Interestingly, fate conversion of fibroblasts to hematoendothelial cells requires not only Scl and Lmo2 but also Gata2, Runx1, and Erg, indicating a necessary collaboration between these transcription factors for hematopoietic reprogramming. Nonetheless, full reprogramming into self-renewing multipotent HSCs may require additional factors and most likely, a permissive microenvironment.
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Affiliation(s)
- T Hoang
- Laboratory of Hematopoiesis and Leukemia, Institute of Research in Immunology and Cancer (IRIC), University of Montreal, Montreal, QC, Canada.
| | - J A Lambert
- Laboratory of Hematopoiesis and Leukemia, Institute of Research in Immunology and Cancer (IRIC), University of Montreal, Montreal, QC, Canada
| | - R Martin
- Laboratory of Hematopoiesis and Leukemia, Institute of Research in Immunology and Cancer (IRIC), University of Montreal, Montreal, QC, Canada
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27
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Sumanas S, Choi K. ETS Transcription Factor ETV2/ER71/Etsrp in Hematopoietic and Vascular Development. Curr Top Dev Biol 2016; 118:77-111. [PMID: 27137655 DOI: 10.1016/bs.ctdb.2016.01.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Effective establishment of the hematopoietic and vascular systems is prerequisite for successful embryogenesis. The ETS transcription factor Etv2 has proven to be essential for hematopoietic and vascular development. Etv2 expression marks the onset of the hematopoietic and vascular development and its deficiency leads to an absolute block in hematopoietic and vascular development. Etv2 is transiently expressed during development and is mainly expressed in testis in adults. Consistent with its expression pattern, Etv2 is transiently required for the generation of the optimal levels of the hemangiogenic cell population. Deletion of this gene after the hemangiogenic progenitor formation leads to normal hematopoietic and vascular development. Mechanistically, ETV2 induces the hemangiogenic program by activating blood and endothelial cell lineage specifying genes and enhancing VEGF signaling. Moreover, ETV2 establishes an ETS hierarchy by directly activating other Ets genes, which in the face of transient Etv2 expression, presumably maintain blood and endothelial cell program initiated by ETV2 through an ETS switching mechanism. Current studies suggest that the hemangiogenic progenitor population is exclusively sensitive to ETV2-dependent FLK1 signaling. Any perturbation in the ETV2, VEGF, and FLK1 balance causing insufficient hemangiogenic progenitor cell generation would lead to defects in hematopoietic and endothelial cell development.
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Affiliation(s)
- S Sumanas
- Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States
| | - K Choi
- Washington University, School of Medicine, St. Louis, MO, United States.
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28
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Fleury M, Eliades A, Carlsson P, Lacaud G, Kouskoff V. FOXF1 inhibits hematopoietic lineage commitment during early mesoderm specification. Development 2015; 142:3307-20. [PMID: 26293303 DOI: 10.1242/dev.124685] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 08/11/2015] [Indexed: 11/20/2022]
Abstract
The molecular mechanisms orchestrating early mesoderm specification are still poorly understood. In particular, how alternate cell fate decisions are regulated in nascent mesoderm remains mostly unknown. In the present study, we investigated both in vitro in differentiating embryonic stem cells, and in vivo in gastrulating embryos, the lineage specification of early mesodermal precursors expressing or not the Forkhead transcription factor FOXF1. Our data revealed that FOXF1-expressing mesoderm is derived from FLK1(+) progenitors and that in vitro this transcription factor is expressed in smooth muscle and transiently in endothelial lineages, but not in hematopoietic cells. In gastrulating embryos, FOXF1 marks most extra-embryonic mesoderm derivatives including the chorion, the allantois, the amnion and a subset of endothelial cells. Similarly to the in vitro situation, FOXF1 expression is excluded from the blood islands and blood cells. Further analysis revealed an inverse correlation between hematopoietic potential and FOXF1 expression in vivo with increased commitment toward primitive erythropoiesis in Foxf1-deficient embryos, whereas FOXF1-enforced expression in vitro was shown to repress hematopoiesis. Altogether, our data establish that during gastrulation, FOXF1 marks all posterior primitive streak extra-embryonic mesoderm derivatives with the remarkable exception of the blood lineage. Our study further suggests that this transcription factor is implicated in actively restraining the specification of mesodermal progenitors to hematopoiesis.
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Affiliation(s)
- Maud Fleury
- Cancer Research UK Stem Cell Hematopoiesis Group, Cancer Research UK Manchester Institute, The University of Manchester, Wilmslow Road, Manchester M20 4BX, UK
| | - Alexia Eliades
- Cancer Research UK Stem Cell Hematopoiesis Group, Cancer Research UK Manchester Institute, The University of Manchester, Wilmslow Road, Manchester M20 4BX, UK
| | - Peter Carlsson
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg 40530, Sweden
| | - Georges Lacaud
- Cancer Research UK Stem Cell Biology Group, Cancer Research UK Manchester Institute, The University of Manchester, Wilmslow Road, Manchester M20 4BX, UK
| | - Valerie Kouskoff
- Cancer Research UK Stem Cell Hematopoiesis Group, Cancer Research UK Manchester Institute, The University of Manchester, Wilmslow Road, Manchester M20 4BX, UK
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29
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Liu F, Li D, Yu YYL, Kang I, Cha MJ, Kim JY, Park C, Watson DK, Wang T, Choi K. Induction of hematopoietic and endothelial cell program orchestrated by ETS transcription factor ER71/ETV2. EMBO Rep 2015; 16:654-69. [PMID: 25802403 DOI: 10.15252/embr.201439939] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 02/26/2015] [Indexed: 11/09/2022] Open
Abstract
The ETS factor ETV2 (aka ER71) is essential for the generation of the blood and vascular system, as ETV2 deficiency leads to a complete block in blood and endothelial cell formation and embryonic lethality in the mouse. However, the ETV2-mediated gene regulatory network and signaling governing hematopoietic and endothelial cell development are poorly understood. Here, we map ETV2 global binding sites and carry out in vitro differentiation of embryonic stem cells, and germ line and conditional knockout mouse studies to uncover mechanisms involved in the hemangiogenic fate commitment from mesoderm. We show that ETV2 binds to enhancers that specify hematopoietic and endothelial cell lineages. We find that the hemangiogenic progenitor population in the developing embryo can be identified as FLK1(high)PDGFRα(-). Notably, these hemangiogenic progenitors are exclusively sensitive to ETV2-dependent FLK1 signaling. Importantly, ETV2 turns on other Ets genes, thereby establishing an ETS hierarchy. Consequently, the hematopoietic and endothelial cell program initiated by ETV2 is maintained partly by other ETS factors through an ETS switching mechanism. These findings highlight the critical role that transient ETV2 expression plays in the regulation of hematopoietic and endothelial cell lineage specification and stability.
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Affiliation(s)
- Fang Liu
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Daofeng Li
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Yik Yeung Lawrence Yu
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Inyoung Kang
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Min-Ji Cha
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Ju Young Kim
- Department of Pediatrics, Children's Heart Research and Outcomes Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Changwon Park
- Department of Pediatrics, Children's Heart Research and Outcomes Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Dennis K Watson
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - Ting Wang
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Kyunghee Choi
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA Developmental, Regenerative, and Stem Cell Biology Program, Washington University School of Medicine, St. Louis, MO, USA
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30
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Moignard V, Woodhouse S, Haghverdi L, Lilly AJ, Tanaka Y, Wilkinson AC, Buettner F, Macaulay IC, Jawaid W, Diamanti E, Nishikawa SI, Piterman N, Kouskoff V, Theis FJ, Fisher J, Göttgens B. Decoding the regulatory network of early blood development from single-cell gene expression measurements. Nat Biotechnol 2015; 33:269-276. [PMID: 25664528 PMCID: PMC4374163 DOI: 10.1038/nbt.3154] [Citation(s) in RCA: 288] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 01/16/2015] [Indexed: 11/16/2022]
Abstract
Reconstruction of the molecular pathways controlling organ development has been hampered by a lack of methods to resolve embryonic progenitor cells. Here we describe a strategy to address this problem that combines gene expression profiling of large numbers of single cells with data analysis based on diffusion maps for dimensionality reduction and network synthesis from state transition graphs. Applying the approach to hematopoietic development in the mouse embryo, we map the progression of mesoderm toward blood using single-cell gene expression analysis of 3,934 cells with blood-forming potential captured at four time points between E7.0 and E8.5. Transitions between individual cellular states are then used as input to develop a single-cell network synthesis toolkit to generate a computationally executable transcriptional regulatory network model of blood development. Several model predictions concerning the roles of Sox and Hox factors are validated experimentally. Our results demonstrate that single-cell analysis of a developing organ coupled with computational approaches can reveal the transcriptional programs that underpin organogenesis.
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Affiliation(s)
- Victoria Moignard
- Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, UK
- Wellcome Trust - Medical Research Council Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| | - Steven Woodhouse
- Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, UK
- Wellcome Trust - Medical Research Council Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| | - Laleh Haghverdi
- Institute of Computational Biology, Helmholtz Zentrum München, Neuherberg, Germany
- Department of Mathematics, Technische Universität München, Garching, Germany
| | - Andrew J. Lilly
- Cancer Research UK Stem Cell Haematopoiesis Group, Paterson Institute for Cancer Research, University of Manchester, Manchester, UK
| | - Yosuke Tanaka
- Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, UK
- Wellcome Trust - Medical Research Council Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
- Laboratory for Stem Cell Biology, RIKEN Center for Developmental Biology, Chuo-ku, Kobe, Japan
| | - Adam C. Wilkinson
- Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, UK
- Wellcome Trust - Medical Research Council Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| | - Florian Buettner
- Institute of Computational Biology, Helmholtz Zentrum München, Neuherberg, Germany
| | - Iain C. Macaulay
- Sanger Institute-EBI Single Cell Genomics Centre, Wellcome Trust Sanger Institute, Hinxton, Cambridge, UK
| | - Wajid Jawaid
- Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, UK
| | - Evangelia Diamanti
- Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, UK
- Wellcome Trust - Medical Research Council Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| | - Shin-Ichi Nishikawa
- Laboratory for Stem Cell Biology, RIKEN Center for Developmental Biology, Chuo-ku, Kobe, Japan
| | - Nir Piterman
- Department of Computer Science, University of Leicester, Leicester, UK
| | - Valerie Kouskoff
- Cancer Research UK Stem Cell Haematopoiesis Group, Paterson Institute for Cancer Research, University of Manchester, Manchester, UK
| | - Fabian J. Theis
- Institute of Computational Biology, Helmholtz Zentrum München, Neuherberg, Germany
- Department of Mathematics, Technische Universität München, Garching, Germany
| | - Jasmin Fisher
- Microsoft Research Cambridge, Cambridge, UK
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Berthold Göttgens
- Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, UK
- Wellcome Trust - Medical Research Council Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
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31
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MiR-24 is required for hematopoietic differentiation of mouse embryonic stem cells. PLoS Genet 2015; 11:e1004959. [PMID: 25634354 PMCID: PMC4310609 DOI: 10.1371/journal.pgen.1004959] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Accepted: 12/16/2014] [Indexed: 11/19/2022] Open
Abstract
Overexpression of miRNA, miR-24, in mouse hematopoietic progenitors increases monocytic/ granulocytic differentiation and inhibits B cell development. To determine if endogenous miR-24 is required for hematopoiesis, we antagonized miR-24 in mouse embryonic stem cells (ESCs) and performed in vitro differentiations. Suppression of miR-24 resulted in an inability to produce blood and hematopoietic progenitors (HPCs) from ESCs. The phenotype is not a general defect in mesoderm production since we observe production of nascent mesoderm as well as mesoderm derived cardiac muscle and endothelial cells. Results from blast colony forming cell (BL-CFC) assays demonstrate that miR-24 is not required for generation of the hemangioblast, the mesoderm progenitor that gives rise to blood and endothelial cells. However, expression of the transcription factors Runx1 and Scl is greatly reduced, suggesting an impaired ability of the hemangioblast to differentiate. Lastly, we observed that known miR-24 target, Trib3, is upregulated in the miR-24 antagonized embryoid bodies (EBs). Overexpression of Trib3 alone in ESCs was able to decrease HPC production, though not as great as seen with miR-24 knockdown. These results demonstrate an essential role for miR-24 in the hematopoietic differentiation of ESCs. Although many miRNAs have been implicated in regulation of hematopoiesis, this is the first miRNA observed to be required for the specification of mammalian blood progenitors from early mesoderm. Studies of mouse embryos and embryonic stem cells (ESCs) have defined the ontogeny of mammalian embryonic hematopoietic cells. The ESC differentiation system has been valuable for dissecting the molecular regulation of the development of mesoderm into HPCs. Extracellular signals regulate a complex network of transcription factors to direct embryonic hematopoietic development. Mammalian miRNAs have previously not been described to regulate this genetic network during embryonic hematopoiesis. However, a role for miRNAs in producing the hemangioblast, and hemogenic endothelium in Xenopus has been described. Our work with ESCs demonstrates a specific requirement for the miRNA, miR-24, in the development of hematopoietic progenitors cells (HPCs). Antagonizing miR-24 in ESCs does not affect generation of BL-CFCs, the in vitro equivalent of the hemangioblast, but does compromise the ability of those BL-CFCs to produced HPCs. Expression of transcription factors required for HPC production downstream of the hemangioblast, Scl, and Runx1, is greatly reduced by antagonizing miR-24. These results identify miR-24, as a mammalian miRNA required for the development of blood from newly formed mesoderm.
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32
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Org T, Duan D, Ferrari R, Montel-Hagen A, Van Handel B, Kerényi MA, Sasidharan R, Rubbi L, Fujiwara Y, Pellegrini M, Orkin SH, Kurdistani SK, Mikkola HK. Scl binds to primed enhancers in mesoderm to regulate hematopoietic and cardiac fate divergence. EMBO J 2015; 34:759-77. [PMID: 25564442 PMCID: PMC4369313 DOI: 10.15252/embj.201490542] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Scl/Tal1 confers hemogenic competence and prevents ectopic cardiomyogenesis in embryonic endothelium by unknown mechanisms. We discovered that Scl binds to hematopoietic and cardiac enhancers that become epigenetically primed in multipotent cardiovascular mesoderm, to regulate the divergence of hematopoietic and cardiac lineages. Scl does not act as a pioneer factor but rather exploits a pre-established epigenetic landscape. As the blood lineage emerges, Scl binding and active epigenetic modifications are sustained in hematopoietic enhancers, whereas cardiac enhancers are decommissioned by removal of active epigenetic marks. Our data suggest that, rather than recruiting corepressors to enhancers, Scl prevents ectopic cardiogenesis by occupying enhancers that cardiac factors, such as Gata4 and Hand1, use for gene activation. Although hematopoietic Gata factors bind with Scl to both activated and repressed genes, they are dispensable for cardiac repression, but necessary for activating genes that enable hematopoietic stem/progenitor cell development. These results suggest that a unique subset of enhancers in lineage-specific genes that are accessible for regulators of opposing fates during the time of the fate decision provide a platform where the divergence of mutually exclusive fates is orchestrated.
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Affiliation(s)
- Tõnis Org
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA, USA
| | - Dan Duan
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA, USA
| | - Roberto Ferrari
- Department of Biological Chemistry, University of California, Los Angeles, CA, USA Eli and Edythe Broad Stem Cell Research Center, University of California, Los Angeles, CA, USA
| | - Amelie Montel-Hagen
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA, USA
| | - Ben Van Handel
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA, USA
| | - Marc A Kerényi
- Department of Pediatric Oncology, Dana-Farber Cancer Institute and Division of Hematology/Oncology, Children's Hospital Boston, Howard Hughes Medical Institute Harvard Stem Cell Institute Harvard Medical School, Boston, MA, USA
| | - Rajkumar Sasidharan
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA, USA
| | - Liudmilla Rubbi
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA, USA
| | - Yuko Fujiwara
- Department of Pediatric Oncology, Dana-Farber Cancer Institute and Division of Hematology/Oncology, Children's Hospital Boston, Howard Hughes Medical Institute Harvard Stem Cell Institute Harvard Medical School, Boston, MA, USA
| | - Matteo Pellegrini
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA, USA
| | - Stuart H Orkin
- Department of Pediatric Oncology, Dana-Farber Cancer Institute and Division of Hematology/Oncology, Children's Hospital Boston, Howard Hughes Medical Institute Harvard Stem Cell Institute Harvard Medical School, Boston, MA, USA
| | - Siavash K Kurdistani
- Department of Biological Chemistry, University of California, Los Angeles, CA, USA Eli and Edythe Broad Stem Cell Research Center, University of California, Los Angeles, CA, USA
| | - Hanna Ka Mikkola
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA, USA Eli and Edythe Broad Stem Cell Research Center, University of California, Los Angeles, CA, USA
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Behrens AN, Zierold C, Shi X, Ren Y, Koyano-Nakagawa N, Garry DJ, Martin CM. Sox7 is regulated by ETV2 during cardiovascular development. Stem Cells Dev 2014; 23:2004-13. [PMID: 24762086 DOI: 10.1089/scd.2013.0525] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Vasculogenesis/angiogenesis is one of the earliest processes that occurs during embryogenesis. ETV2 and SOX7 were previously shown to play a role in endothelial development; however, their mechanistic interaction has not been defined. In the present study, concomitant expression of Etv2 and Sox7 in endothelial progenitor cells was verified. ETV2 was shown to be a direct upstream regulator of Sox7 that binds to ETV2 binding elements in the Sox7 upstream regulatory region and activates transcription. We observed that SOX7 over-expression can mimic ETV2 and increase endothelial progenitor cells in embryonic bodies (EBs), while knockdown of Sox7 is able to block ETV2-induced increase in endothelial progenitor cell formation. Angiogenic sprouting was increased by ETV2 over-expression in EBs, and it was significantly decreased in the presence of Sox7 shRNA. Collectively, these studies support the conclusion that ETV2 directly regulates Sox7, and that ETV2 governs endothelial development by regulating transcriptional networks which include Sox7.
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Affiliation(s)
- Ann N Behrens
- Lillehei Heart Institute, University of Minnesota , Minneapolis, Minnesota
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Abedin MJ, Nguyen A, Jiang N, Perry CE, Shelton JM, Watson DK, Ferdous A. Fli1 acts downstream of Etv2 to govern cell survival and vascular homeostasis via positive autoregulation. Circ Res 2014; 114:1690-9. [PMID: 24727028 DOI: 10.1161/circresaha.1134303145] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
RATIONALE Cardiovascular health depends on proper development and integrity of blood vessels. Ets variant 2 (Etv2), a member of the E26 transforming-specific family of transcription factors, is essential to initiate a transcriptional program leading to vascular morphogenesis in early mouse embryos. However, endothelial expression of the Etv2 gene ceases at midgestation; therefore, vascular development past this stage must continue independent of Etv2. OBJECTIVE To identify molecular mechanisms underlying transcriptional regulation of vascular morphogenesis and homeostasis in the absence of Etv2. METHODS AND RESULTS Using loss- and gain-of-function strategies and a series of molecular techniques, we identify Friend leukemia integration 1 (Fli1), another E26 transforming-specific family transcription factor, as a downstream target of Etv2. We demonstrate that Etv2 binds to conserved Ets-binding sites within the promoter region of the Fli1 gene and governs Fli1 expression. Importantly, in the absence of Etv2 at midgestation, binding of Etv2 at Ets-binding sites in the Fli1 promoter is replaced by Fli1 protein itself, sustaining expression of Fli1 as well as selective Etv2-regulated endothelial genes to promote endothelial cell survival and vascular integrity. Consistent with this, we report that Fli1 binds to the conserved Ets-binding sites within promoter and enhancer regions of other Etv2-regulated endothelial genes, including Tie2, to control their expression at and beyond midgestation. CONCLUSIONS We have identified a novel positive feed-forward regulatory loop in which Etv2 activates expression of genes involved in vasculogenesis, including Fli1. Once the program is activated in early embryos, Fli1 then takes over to sustain the process in the absence of Etv2.
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Affiliation(s)
- Md J Abedin
- From the Department of Internal Medicine (Cardiology) (M.J.A., A.N., N.J., C.E.P., J.M.S., A.F.), University of Texas Southwestern Medical Center, Dallas; Department of Pathology and Laboratory Medicine, Hollings Cancer Center, Medical University of South Carolina, Charleston (D.K.W.); and Division of Hematology, Oncology, and Transplantation, Department of Medicine, University of Minnesota, Minneapolis (M.J.A.)
| | - Annie Nguyen
- From the Department of Internal Medicine (Cardiology) (M.J.A., A.N., N.J., C.E.P., J.M.S., A.F.), University of Texas Southwestern Medical Center, Dallas; Department of Pathology and Laboratory Medicine, Hollings Cancer Center, Medical University of South Carolina, Charleston (D.K.W.); and Division of Hematology, Oncology, and Transplantation, Department of Medicine, University of Minnesota, Minneapolis (M.J.A.)
| | - Nan Jiang
- From the Department of Internal Medicine (Cardiology) (M.J.A., A.N., N.J., C.E.P., J.M.S., A.F.), University of Texas Southwestern Medical Center, Dallas; Department of Pathology and Laboratory Medicine, Hollings Cancer Center, Medical University of South Carolina, Charleston (D.K.W.); and Division of Hematology, Oncology, and Transplantation, Department of Medicine, University of Minnesota, Minneapolis (M.J.A.)
| | - Cameron E Perry
- From the Department of Internal Medicine (Cardiology) (M.J.A., A.N., N.J., C.E.P., J.M.S., A.F.), University of Texas Southwestern Medical Center, Dallas; Department of Pathology and Laboratory Medicine, Hollings Cancer Center, Medical University of South Carolina, Charleston (D.K.W.); and Division of Hematology, Oncology, and Transplantation, Department of Medicine, University of Minnesota, Minneapolis (M.J.A.)
| | - John M Shelton
- From the Department of Internal Medicine (Cardiology) (M.J.A., A.N., N.J., C.E.P., J.M.S., A.F.), University of Texas Southwestern Medical Center, Dallas; Department of Pathology and Laboratory Medicine, Hollings Cancer Center, Medical University of South Carolina, Charleston (D.K.W.); and Division of Hematology, Oncology, and Transplantation, Department of Medicine, University of Minnesota, Minneapolis (M.J.A.)
| | - Dennis K Watson
- From the Department of Internal Medicine (Cardiology) (M.J.A., A.N., N.J., C.E.P., J.M.S., A.F.), University of Texas Southwestern Medical Center, Dallas; Department of Pathology and Laboratory Medicine, Hollings Cancer Center, Medical University of South Carolina, Charleston (D.K.W.); and Division of Hematology, Oncology, and Transplantation, Department of Medicine, University of Minnesota, Minneapolis (M.J.A.)
| | - Anwarul Ferdous
- From the Department of Internal Medicine (Cardiology) (M.J.A., A.N., N.J., C.E.P., J.M.S., A.F.), University of Texas Southwestern Medical Center, Dallas; Department of Pathology and Laboratory Medicine, Hollings Cancer Center, Medical University of South Carolina, Charleston (D.K.W.); and Division of Hematology, Oncology, and Transplantation, Department of Medicine, University of Minnesota, Minneapolis (M.J.A.).
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Cooperative interaction of Etv2 and Gata2 regulates the development of endothelial and hematopoietic lineages. Dev Biol 2014; 389:208-18. [PMID: 24583263 DOI: 10.1016/j.ydbio.2014.02.018] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 02/07/2014] [Accepted: 02/19/2014] [Indexed: 12/31/2022]
Abstract
Regulatory mechanisms that govern lineage specification of the mesodermal progenitors to become endothelial and hematopoietic cells remain an area of intense interest. Both Ets and Gata factors have been shown to have important roles in the transcriptional regulation in endothelial and hematopoietic cells. We previously reported Etv2 as an essential regulator of vasculogenesis and hematopoiesis. In the present study, we demonstrate that Gata2 is co-expressed and interacts with Etv2 in the endothelial and hematopoietic cells in the early stages of embryogenesis. Our studies reveal that Etv2 interacts with Gata2 in vitro and in vivo. The protein-protein interaction between Etv2 and Gata2 is mediated by the Ets and Gata domains. Using the embryoid body differentiation system, we demonstrate that co-expression of Gata2 augments the activity of Etv2 in promoting endothelial and hematopoietic lineage differentiation. We also identify Spi1 as a common downstream target gene of Etv2 and Gata2. We provide evidence that Etv2 and Gata2 bind to the Spi1 promoter in vitro and in vivo. In summary, we propose that Gata2 functions as a cofactor of Etv2 in the transcriptional regulation of mesodermal progenitors during embryogenesis.
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36
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Ciau-Uitz A, Wang L, Patient R, Liu F. ETS transcription factors in hematopoietic stem cell development. Blood Cells Mol Dis 2013; 51:248-55. [DOI: 10.1016/j.bcmd.2013.07.010] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Accepted: 07/04/2013] [Indexed: 01/08/2023]
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Moore JC, Sheppard-Tindell S, Shestopalov IA, Yamazoe S, Chen JK, Lawson ND. Post-transcriptional mechanisms contribute to Etv2 repression during vascular development. Dev Biol 2013; 384:128-40. [PMID: 24036310 DOI: 10.1016/j.ydbio.2013.08.028] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 08/05/2013] [Accepted: 08/30/2013] [Indexed: 01/08/2023]
Abstract
etv2 is an endothelial-specific ETS transcription factor that is essential for vascular differentiation and morphogenesis in vertebrates. While recent data suggest that Etv2 is dynamically regulated during vascular development, little is known about the mechanisms involved in this process. Here, we find that etv2 transcript and protein expression are highly dynamic during zebrafish vascular development, with both apparent during early somitogenesis and subsequently down-regulated as development proceeds. Inducible knockdown of Etv2 in zebrafish embryos prior to mid-somitogenesis stages, but not later, caused severe vascular defects, suggesting a specific role in early commitment of lateral mesoderm to the endothelial linage. Accordingly, Etv2-overexpressing cells showed an enhanced ability to commit to endothelial lineages in mosaic embryos. We further find that the etv2 3' untranslated region (UTR) is capable of repressing an endothelial autonomous transgene and contains binding sites for members of the let-7 family of microRNAs. Ectopic expression of let-7a could repress the etv2 3'UTR in sensor assays and was also able to block endogenous Etv2 protein expression, leading to concomitant reduction of endothelial genes. Finally, we observed that Etv2 protein levels persisted in maternal-zygotic dicer1 mutant embryos, suggesting that microRNAs contribute to its repression during vascular development. Taken together, our results suggest that etv2 acts during early development to specify endothelial lineages and is then down-regulated, in part through post-transcriptional repression by microRNAs, to allow normal vascular development.
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Affiliation(s)
- John C Moore
- Program in Gene Function and Expression, University of Massachusetts Medical School, Worcester, MA 01605, USA.
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38
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Moignard V, Woodhouse S, Fisher J, Göttgens B. Transcriptional hierarchies regulating early blood cell development. Blood Cells Mol Dis 2013; 51:239-47. [PMID: 23948234 DOI: 10.1016/j.bcmd.2013.07.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 06/25/2013] [Indexed: 11/15/2022]
Abstract
Hematopoiesis represents one of the paradigmatic systems for studying stem cell biology, but our understanding of how the hematopoietic system develops during embryogenesis is still incomplete. While many lessons have been learned from studying the mouse embryo, embryonic stem cells have come to the fore as an alternative and more tractable model to recapitulate hematopoietic development. Here we review what is known about the embryonic origin of blood from these complementary systems and how transcription factor networks regulate the emergence of hematopoietic tissue from the mesoderm. Furthermore, we have performed an integrated analysis of genome-wide microarray and ChIP-seq data sets from mouse embryos and embryonic stem (ES) cell lines deficient in key regulators and demonstrate how this type of analysis can be used to reconstruct regulatory hierarchies that both confirm existing regulatory linkages and suggest additional interactions.
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Affiliation(s)
- Victoria Moignard
- University of Cambridge, Department of Haematology, Wellcome Trust and MRC Cambridge Stem Cell Institute and Cambridge Institute for Medical Research, Cambridge, CB2 0XY, UK
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Kobayashi K, Ding G, Nishikawa SI, Kataoka H. Role of Etv2-positive cells in the remodeling morphogenesis during vascular development. Genes Cells 2013; 18:704-21. [PMID: 23795570 DOI: 10.1111/gtc.12070] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 05/02/2013] [Indexed: 01/12/2023]
Abstract
Etv2 is a critical determinant for the commitment of endothelial (EC) and hematopoietic (HPC) cells from mesoderm. Etv2 is assumed to be transiently required for EC commitment but dispensable after most ECs differentiate around E9.5. To confirm the time window of Etv2 requirement, Etv2 was ablated at different time points using ROSA26CreER mice. Unexpectedly, Etv2 ablation at E9.5 caused vascular remodeling defects in cranial and yolk sac vasculature. Immunostaining showed that Etv2+/VE-cadherin (VECAD)- cells were present around forming vasculature, mostly co-expressing Flk-1 with a small number of Etv2+/VECAD+ cells, indicating that Etv2+/Flk-1+/VECAD- cells are the major Etv2+ population promoting vascular remodeling around E9.5. Gene expression analysis showed up-regulation of Fgf proteins, Il-6, Glypican-3 and matrix metalloproteases in Etv2+/VEDAC- cells over Etv2-/VECAD+ mature ECs. Blockade of those factors caused reduced EC sprouting in ex vivo explant culture from E9.5 embryos, suggesting the functional significance of environmental factors derived from Etv2+ cells. Altogether, we propose that Etv2+/VEDAC- cells around E9.5-E10.5 provide extracellular factors to complete vascular morphogenesis in addition to becoming differentiated ECs incorporated into vessels. This insight for the new role of Ets protein in perivascular Flk-1+/VECAD-/(Etv2+) cells to induce expression of angiogenic factors may provide another strategy to control angiogenesis.
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Affiliation(s)
- Kumiko Kobayashi
- Laboratory for Stem Cell Biology, RIKEN Center for Developmental Biology, 2-2-3 Minatojima-Minamimachi, Chuo-ku, Kobe 650-0047, Japan
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40
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Abstract
The circulatory system is the first organ system to develop in the vertebrate embryo and is critical throughout gestation for the delivery of oxygen and nutrients to, as well as removal of metabolic waste products from, growing tissues. Endothelial cells, which constitute the luminal layer of all blood and lymphatic vessels, emerge de novo from the mesoderm in a process known as vasculogenesis. The vascular plexus that is initially formed is then remodeled and refined via proliferation, migration, and sprouting of endothelial cells to form new vessels from preexisting ones during angiogenesis. Mural cells are also recruited by endothelial cells to form the surrounding vessel wall. During this vascular remodeling process, primordial endothelial cells are specialized to acquire arterial, venous, and blood-forming hemogenic phenotypes and functions. A subset of venous endothelium is also specialized to become lymphatic endothelium later in development. The specialization of all endothelial cell subtypes requires extrinsic signals and intrinsic regulatory events, which will be discussed in this review.
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Affiliation(s)
- Kathrina L Marcelo
- Interdepartmental Program in Developmental Biology, Baylor College of Medicine, Houston, TX, USA
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41
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Veldman MB, Zhao C, Gomez GA, Lindgren AG, Huang H, Yang H, Yao S, Martin BL, Kimelman D, Lin S. Transdifferentiation of fast skeletal muscle into functional endothelium in vivo by transcription factor Etv2. PLoS Biol 2013; 11:e1001590. [PMID: 23853546 PMCID: PMC3708712 DOI: 10.1371/journal.pbio.1001590] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Accepted: 05/09/2013] [Indexed: 02/05/2023] Open
Abstract
Etv2, a master regulator of endothelial cell fate, can induce fast skeletal muscle cells to transdifferentiate into endothelial cells in the zebrafish embryo. Etsrp/Etv2 (Etv2) is an evolutionarily conserved master regulator of vascular development in vertebrates. Etv2 deficiency prevents the proper specification of the endothelial cell lineage, while its overexpression causes expansion of the endothelial cell lineage in the early embryo or in embryonic stem cells. We hypothesized that Etv2 alone is capable of transdifferentiating later somatic cells into endothelial cells. Using heat shock inducible Etv2 transgenic zebrafish, we demonstrate that Etv2 expression alone is sufficient to transdifferentiate fast skeletal muscle cells into functional blood vessels. Following heat treatment, fast skeletal muscle cells turn on vascular genes and repress muscle genes. Time-lapse imaging clearly shows that muscle cells turn on vascular gene expression, undergo dramatic morphological changes, and integrate into the existing vascular network. Lineage tracing and immunostaining confirm that fast skeletal muscle cells are the source of these newly generated vessels. Microangiography and observed blood flow demonstrated that this new vasculature is capable of supporting circulation. Using pharmacological, transgenic, and morpholino approaches, we further establish that the canonical Wnt pathway is important for induction of the transdifferentiation process, whereas the VEGF pathway provides a maturation signal for the endothelial fate. Additionally, overexpression of Etv2 in mammalian myoblast cells, but not in other cell types examined, induced expression of vascular genes. We have demonstrated in zebrafish that expression of Etv2 alone is sufficient to transdifferentiate fast skeletal muscle into functional endothelial cells in vivo. Given the evolutionarily conserved function of this transcription factor and the responsiveness of mammalian myoblasts to Etv2, it is likely that mammalian muscle cells will respond similarly. The endothelial cell is a specialized cell type that lines blood vessels. These cells are involved in normal cardiovascular function and become damaged in cardiovascular disease states such as atherosclerosis and stroke. We have discovered that developing muscle cells in the zebrafish embryo can be converted into endothelial cells by the expression of a transcription factor called Etv2. Etv2 normally functions during embryonic development to specify blood and blood vessels. When expressed in muscle cells, Etv2 induces the expression of genes that are normally expressed in endothelial cells; it also represses muscle gene expression. On expressing Etv2, muscle cells change shape and go on to form lumenized blood vessels that connect to the existing circulatory system and support blood flow. The Wnt and VEGF signaling pathways are required for this fate transformation. Our results suggest that muscle cells may be a viable source for the de novo generation of endothelial cells for use in transplantation therapies and they highlight signalling pathways that might be manipulated to improve the efficiency of this process in mammalian cells.
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Affiliation(s)
- Matthew B. Veldman
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan, People's Republic of China
- Department of Molecular, Cell and Developmental Biology, University of California–Los Angeles, Los Angeles, California, United States of America
| | - Chengjian Zhao
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan, People's Republic of China
- Department of Molecular, Cell and Developmental Biology, University of California–Los Angeles, Los Angeles, California, United States of America
| | - Gustavo A. Gomez
- Department of Molecular, Cell and Developmental Biology, University of California–Los Angeles, Los Angeles, California, United States of America
| | - Anne G. Lindgren
- Department of Molecular, Cell and Developmental Biology, University of California–Los Angeles, Los Angeles, California, United States of America
| | - Haigen Huang
- Department of Molecular, Cell and Developmental Biology, University of California–Los Angeles, Los Angeles, California, United States of America
| | - Hanshuo Yang
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan, People's Republic of China
- Department of Molecular, Cell and Developmental Biology, University of California–Los Angeles, Los Angeles, California, United States of America
| | - Shaohua Yao
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan, People's Republic of China
- Department of Molecular, Cell and Developmental Biology, University of California–Los Angeles, Los Angeles, California, United States of America
| | - Benjamin L. Martin
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, New York, United States of America
- Department of Biochemistry, University of Washington, Seattle, Washington, United States of America
| | - David Kimelman
- Department of Biochemistry, University of Washington, Seattle, Washington, United States of America
| | - Shuo Lin
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan, People's Republic of China
- Department of Molecular, Cell and Developmental Biology, University of California–Los Angeles, Los Angeles, California, United States of America
- * E-mail:
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42
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Kataoka H, Hayashi M, Kobayashi K, Ding G, Tanaka Y, Nishikawa SI. Region-specific Etv2 ablation revealed the critical origin of hemogenic capacity from Hox6-positive caudal-lateral primitive mesoderm. Exp Hematol 2013; 41:567-581.e9. [DOI: 10.1016/j.exphem.2013.02.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 02/16/2013] [Indexed: 02/08/2023]
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Ding G, Tanaka Y, Hayashi M, Nishikawa SI, Kataoka H. PDGF receptor alpha+ mesoderm contributes to endothelial and hematopoietic cells in mice. Dev Dyn 2013; 242:254-68. [PMID: 23335233 PMCID: PMC3597973 DOI: 10.1002/dvdy.23923] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Revised: 12/12/2012] [Accepted: 12/20/2012] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND Early mesoderm can be classified into Flk-1+ or PDGF receptor alpha (PDGFRα)+ population, grossly representing lateral and paraxial mesoderm, respectively. It has been demonstrated that all endothelial (EC) and hematopoietic (HPC) cells are derived from Flk-1+ cells. Although PDGFRα+ cells give rise to ECs/HPCs in in vitro ES differentiation, whether PDGFRα+ population can become hemato-endothelial lineages has not been proved in mouse embryos. RESULTS Using PDGFRαMerCreMer mice, PDGFRα+ early mesoderm was shown to contribute to endothelial cells including hemogenic ECs, fetal liver B lymphocytes, and Lin-Kit+Sca-1+ (KSL) cells. Contribution of PDGFRα+ mesoderm into ECs and HPCs was limited until E8.5, indicating that PDGFRα+/Flk-1+ population that exists until E8.5 may be the source for hemato-endothelial lineages from PDGFRα+ population. The functional significance of PDGFRα+ mesoderm in vascular development and hematopoiesis was confirmed by genetic deletion of Etv2 or restoration of Runx1 in PDGFRα+ cells. Etv2 deletion and Runx1 restoration in PDGFRα+ cells resulted in abnormal vascular remodeling and rescue of fetal liver CD45+ and Lin-Kit+Sca-1+ (KSL) cells, respectively. CONCLUSIONS Endothelial and hematopoietic cells can be derived from PDGFRα+ early mesoderm in mice. PDGFRα+ mesoderm is functionally significant in vascular development and hematopoiesis from phenotype analysis of genetically modified embryos.
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Affiliation(s)
- Guo Ding
- Laboratory for Stem Cell Biology, RIKEN Center for Developmental Biology, Kobe, Japan
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Rasmussen TL, Shi X, Wallis A, Kweon J, Zirbes KM, Koyano-Nakagawa N, Garry DJ. VEGF/Flk1 signaling cascade transactivates Etv2 gene expression. PLoS One 2012. [PMID: 23185546 PMCID: PMC3501484 DOI: 10.1371/journal.pone.0050103] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Previous reports regarding the genetic hierarchy between Ets related protein 71 (Er71/Etv2) and Flk1 is unclear. In the present study, we pursued a genetic approach to define the molecular cascade between Etv2 and Flk1. Using a transgenic Etv2-EYFP reporter mouse, we examined the expression pattern of Etv2 relative to Flk1 in the early conceptus. Etv2-EYFP was expressed in subset of Flk1 positive cells during primitive streak stages, suggesting that Flk1 is upstream of Etv2 during gastrulation. Analysis of reporter gene expression in Flk1 and Etv2 mutant mice further supports the hypothesis that Flk1 is necessary for Etv2 expression. The frequency of cells expressing Flk1 in Etv2 mutants is only modestly altered (21% decrease), whereas expression of the Etv2-EYFP transgenic reporter was severely reduced in the Flk1 null background. We further demonstrate using transcriptional assays that, in the presence of Flk1, the Etv2 promoter is activated by VEGF, the Flk1 ligand. Pharmacological inhibition studies demonstrate that VEGF mediated activation is dependent on p38 MAPK, which activates Creb. We identify the VEGF response element in the Etv2 promoter and demonstrate that Creb binds to this motif by EMSA and ChIP assays. In summary, we provide new evidence that VEGF activates Etv2 by signaling through Flk1, which activates Creb through the p38 MAPK signaling cascade.
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Affiliation(s)
- Tara L. Rasmussen
- Lillehei Heart Institute, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Xiaozhong Shi
- Lillehei Heart Institute, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Alicia Wallis
- Lillehei Heart Institute, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Junghun Kweon
- Lillehei Heart Institute, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Katie M. Zirbes
- Lillehei Heart Institute, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Naoko Koyano-Nakagawa
- Lillehei Heart Institute, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Daniel J. Garry
- Lillehei Heart Institute, University of Minnesota, Minneapolis, Minnesota, United States of America
- * E-mail:
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Wareing S, Eliades A, Lacaud G, Kouskoff V. ETV2 expression marks blood and endothelium precursors, including hemogenic endothelium, at the onset of blood development. Dev Dyn 2012; 241:1454-64. [PMID: 22733530 DOI: 10.1002/dvdy.23825] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/12/2012] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND ETV2 has been identified as an important player in embryonic hematopoiesis. However, the cell populations in which this transcription factor is expressed and operates during blood specification remain to be fully characterized. Here we address these issues using ES cells and a transgenic mouse line expressing green fluorescent protein (GFP) under the control of ETV2 regulatory elements, allowing us to observe the tight association between ETV2 expression and the initiation of hematopoiesis. RESULTS Both in differentiating ES cells and gastrulating embryos ETV2::GFP is mostly found co-expressed with endothelial markers and defines a subset of cells with greatly enriched primitive erythroid potential. Upon culture ETV2::GFP cells rapidly up-regulate CD41, down-regulate endothelium cell surface markers and generate definitive hematopoietic progenitors. Altogether these characteristics represent the hallmark of hemogenic endothelium cells, a specialized endothelium originating from the hemangioblast and giving rise to hematopoietic cells. Importantly, ETV2 deficiency results in a complete absence of hemogenic endothelium in differentiating ES cells and gastrulating embryos. CONCLUSIONS Altogether our data reveal that ETV2 marks hemogenic endothelium in gastrulating embryos and is absolutely required for the formation of this precursor at the onset of hematopoiesis. These results enhance our understanding of embryonic hematopoiesis and the factors driving hemogenic endothelium specification.
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Affiliation(s)
- Sarah Wareing
- Cancer Research UK Stem Cell Hematopoiesis Group, Paterson Institute for Cancer Research, University of Manchester, Manchester, UK
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